De-multiplexing a radio frequency input signal using output transformer circuitry

ABSTRACT

The present disclosure relates to de-multiplexing at least one RF input signal feeding RF power amplifier circuitry to create multiple de-multiplexed RF output signals, which may be used to provide RF transmit signals in an RF communications system. Output transformer circuitry is coupled to outputs from the RF power amplifier circuitry to provide the de-multiplexed RF output signals, which may support multiple modes, multiple frequency bands, or both. The de-multiplexed RF output signals may be used in place of RF switching elements in certain embodiments. As a result, RF front-end switching circuitry in the RF communications system may be simplified, thereby reducing insertion losses, reducing costs, reducing size, or any combination thereof. Additionally, the output transformer circuitry may provide load line transformation, output transistor biasing, or both to the RF power amplifier circuitry.

The present application claims priority to and is a continuation of U.S.patent application Ser. No. 12/966,707, filed Dec. 13, 2010, entitled“DE-MULTIPLEXING A RADIO FREQUENCY INPUT SIGNAL USING OUTPUT TRANSFORMERCIRCUITRY,” now U.S. Pat. No. 8,570,913, which claims priority to U.S.Provisional Patent Application No. 61/285,782, filed Dec. 11, 2009. Bothof the applications listed above are hereby incorporated herein byreference in their entireties.

FIELD OF THE DISCLOSURE

Embodiments of the present disclosure relate to output transformercircuitry coupled to outputs from radio frequency (RF) power amplifiercircuitry, both of which may be used in wireless communications systems.

BACKGROUND OF THE DISCLOSURE

As wireless communications technologies evolve, wireless communicationssystems become increasingly sophisticated. Multi-mode and multi-bandwireless systems are routinely available. Such systems may includecircuit elements to support multiple modes, multiple frequency bands, orboth. Typical multi-mode communications systems may communicate using atleast one of two different modes of operation. The first mode, calledhalf duplex, is a two-way mode of operation, in which a firsttransceiver communicates with a second transceiver; however, only onetransceiver transmits at a time. Therefore, the transmitter and receiverin a transceiver do not operate simultaneously. For example, certaintelemetry systems operate in a send-then-wait-for-reply manner. Manytime division duplex (TDD) systems operate using a half duplex mode.

The second mode, called full duplex, is a simultaneous two-way mode ofoperation, in which a first transceiver communicates with a secondtransceiver, and both transceivers may transmit simultaneously;therefore, the transmitter and receiver in a transceiver must be capableof operating simultaneously. In a full duplex transceiver, signals fromthe transmitter must not interfere with signals received by thereceiver; therefore, transmitted signals are at transmit frequenciesthat are different from received signals, which are at receivefrequencies. Many frequency division duplex (FDD) systems operate usinga full duplex mode.

As a result of the differences between full duplex operation and halfduplex operation, RF front end circuitry may need specific circuitry foreach mode. As a result, the RF front end circuitry may need separatesignals for each mode. Additionally, support of multiple frequency bandsmay require specific circuitry for each frequency band or for certaingroupings of frequency bands. As a result, the RF front end circuitrymay need separate signals based on which frequency bands are in use. Inorder to reduce size and cost, and increase performance and efficiency,multi-mode and multi-band wireless systems need to support multiplemodes, multiple bands, or both in a way to reduce size, cost, andinsertion losses. Thus, there is a need for a wireless system that caneffectively generate the separate signals needed for multi-modeoperation, multi-band operation, or both.

SUMMARY OF THE EMBODIMENTS

The present disclosure relates to de-multiplexing at least one RF inputsignal feeding RF power amplifier circuitry to create multiplede-multiplexed RF output signals, which may be used to provide RFtransmit signals in an RF communications system. Output transformercircuitry is coupled to outputs from the RF power amplifier circuitry toprovide the de-multiplexed RF output signals, which may support multiplemodes, multiple frequency bands, or both. The de-multiplexed RF outputsignals may be used in place of RF switching elements in certainembodiments. As a result, RF front-end switching circuitry in the RFcommunications system may be simplified, thereby reducing insertionlosses, reducing costs, reducing size, or any combination thereof.Additionally, the output transformer circuitry may provide load linetransformation, output transistor biasing, or both to the RF poweramplifier circuitry.

Those skilled in the art will appreciate the scope of the presentdisclosure and realize additional aspects thereof after reading thefollowing detailed description of the preferred embodiments inassociation with the accompanying drawing figures.

BRIEF DESCRIPTION OF THE DRAWING FIGURES

The accompanying drawing figures incorporated in and forming a part ofthis specification illustrate several aspects of the disclosure, andtogether with the description serve to explain the principles of thedisclosure.

FIG. 1 shows RF circuitry according to one embodiment of the RFcircuitry.

FIG. 2 shows details of input transformer circuitry, input switchingcircuitry, differential RF power amplifier circuitry, and outputtransformer circuitry illustrated in FIG. 1 according to one embodimentof the input transformer circuitry, the input switching circuitry, thedifferential RF power amplifier circuitry, and the output transformercircuitry.

FIG. 3 shows details of the RF circuitry illustrated in FIG. 2 during afirst operating mode of the RF circuitry.

FIG. 4 shows details of the RF circuitry illustrated in FIG. 2 during asecond operating mode of the RF circuitry.

FIG. 5 shows the RF circuitry according to an alternate embodiment ofthe RF circuitry.

FIG. 6 shows the RF circuitry according to an additional embodiment ofthe RF circuitry.

FIG. 7 shows details of the RF circuitry illustrated in FIG. 6 duringthe first operating mode of the RF circuitry.

FIG. 8 shows details of the RF circuitry illustrated in FIG. 6 duringthe second operating mode of the RF circuitry.

FIG. 9 shows details of the RF circuitry illustrated in FIG. 6 during athird operating mode of the RF circuitry.

FIG. 10 shows details of the RF circuitry illustrated in FIG. 6 during afourth operating mode of the RF circuitry.

FIG. 11 shows the RF circuitry according to another embodiment of the RFcircuitry.

FIG. 12 shows details of the differential RF power amplifier circuitryillustrated in FIG. 1 according to one embodiment of the differential RFpower amplifier circuitry.

FIG. 13 shows the RF circuitry according to one embodiment of the RFcircuitry.

FIG. 14 shows the RF circuitry according to an alternate embodiment ofthe RF circuitry.

FIG. 15 shows the RF circuitry according to an additional embodiment ofthe RF circuitry.

FIG. 16 shows the RF circuitry according to another embodiment of the RFcircuitry.

FIG. 17 shows details of a portion of output transformer circuitryillustrated in FIG. 2 according to one embodiment of the portion of theoutput transformer circuitry.

FIG. 18 shows the RF circuitry according to a further embodiment of theRF circuitry.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The embodiments set forth below represent the necessary information toenable those skilled in the art to practice the disclosure andillustrate the best mode of practicing the disclosure. Upon reading thefollowing description in light of the accompanying drawing figures,those skilled in the art will understand the concepts of the disclosureand will recognize applications of these concepts not particularlyaddressed herein. It should be understood that these concepts andapplications fall within the scope of the disclosure and theaccompanying claims.

The present disclosure relates to de-multiplexing at least one RF inputsignal feeding RF power amplifier circuitry to create multiplede-multiplexed RF output signals, which may be used to provide RFtransmit signals in an RF communications system. Output transformercircuitry is coupled to outputs from the RF power amplifier circuitry toprovide the de-multiplexed RF output signals, which may support multiplemodes, multiple frequency bands, or both. The de-multiplexed RF outputsignals may be used in place of RF switching elements in certainembodiments. As a result, RF front-end switching circuitry in the RFcommunications system may be simplified, thereby reducing insertionlosses, reducing costs, reducing size, or any combination thereof.Additionally, the output transformer circuitry may provide load linetransformation, output transistor biasing, or both to the RF poweramplifier circuitry.

FIG. 1 shows RF circuitry 10 according to one embodiment of the RFcircuitry 10. The RF circuitry 10 includes control circuitry 12, inputtransformer circuitry 14, input switching circuitry 16, differential RFpower amplifier circuitry 18, and output transformer circuitry 20.During operation, the control circuitry 12 may select one of multipleoperating modes, which may include a first operating mode and a secondoperating mode. The control circuitry 12 provides a mode select signalMSS to the input switching circuitry 16. The mode select signal MSS maybe indicative of which of the multiple operating modes is selected. Ingeneral, the mode select signal MSS is based on which of the multipleoperating modes is selected.

The input transformer circuitry 14 receives and splits a transformerinput signal TIS to provide a first differential RF switching signal anda second differential RF switching signal to the input switchingcircuitry 16. The first differential RF switching signal includes afirst positive-side RF switching signal SS1P and a first negative-sideRF switching signal SS1N, and the second differential RF switchingsignal includes a second positive-side RF switching signal SS2P and asecond negative-side RF switching signal SS2N. The first positive-sideRF switching signal SS1P may be phase-shifted about 180 degrees from thefirst negative-side RF switching signal SS1N and the secondpositive-side RF switching signal SS2P may be phase-shifted about 180degrees from the second negative-side RF switching signal SS2N. In oneembodiment of the RF circuitry 10, the transformer input signal TIS is asingle-ended signal. In an alternate embodiment of the RF circuitry 10,the transformer input signal TIS is a differential signal. The inputtransformer circuitry 14 may split the power provided by the transformerinput signal TIS to provide the first differential RF switching signaland the second differential RF switching signal. As such, the powerprovided by the first differential RF switching signal may be aboutequal to the power provided by the second differential RF switchingsignal. The input transformer circuitry 14 may be used to provide loadline transformation.

The input switching circuitry 16 receives and forwards the firstdifferential RF switching signal to provide a first differential RFinput signal based on the mode select signal MSS, and the inputswitching circuitry 16 receives and forwards the second differential RFswitching signal to provide a second differential RF input signal basedon the mode select signal MSS. The first differential RF input signalincludes a first positive-side RF input signal IS1P and a firstnegative-side RF input signal IS1N, and the second differential RF inputsignal includes a second positive-side RF input signal IS2P and a secondnegative-side RF input signal IS2N. The first positive-side RF inputsignal IS1P may be phase-shifted from the first negative-side RF inputsignal IS1N by about 180 degrees and the second positive-side RF inputsignal IS2P may be phase-shifted from the second negative-side RF inputsignal IS2N by about 180 degrees.

Depending on the mode select signal MSS, the input switching circuitry16 may receive and forward the first positive-side RF switching signalSS1P to provide the first positive-side RF input signal IS1P, andreceive and forward the first negative-side RF switching signal SS1N toprovide the first negative-side RF input signal IS1N. Alternatively,depending on the mode select signal MSS, the input switching circuitry16 may receive and forward the first positive-side RF switching signalSS1P to provide the first negative-side RF input signal IS1N, andreceive and forward the first negative-side RF switching signal SS1N toprovide the first positive-side RF input signal IS1P.

Similarly, depending on the mode select signal MSS, the input switchingcircuitry 16 may receive and forward the second positive-side RFswitching signal SS2P to provide the second positive-side RF inputsignal IS2P, and receive and forward the second negative-side RFswitching signal SS2N to provide the second negative-side RF inputsignal IS2N. Alternatively, depending on the mode select signal MSS, theinput switching circuitry 16 may receive and forward the secondpositive-side RF switching signal SS2P to provide the secondnegative-side RF input signal IS2N, and receive and forward the secondnegative-side RF switching signal SS2N to provide the secondpositive-side RF input signal IS2P. In general, the first differentialRF input signal and the second differential RF input signal are based onsplitting the transformer input signal TIS.

The differential RF power amplifier circuitry 18 receives and amplifiesthe first differential RF input signal to provide a first differentialRF output signal, and receives and amplifies the second differential RFinput signal to provide a second differential RF output signal. Thefirst differential RF output signal includes a first positive-side RFoutput signal OS1P and a first negative-side RF output signal OS1N, andthe second differential RF output signal includes a second positive-sideRF output signal OS2P and a second negative-side RF output signal OS2N.The first positive-side RF output signal OS1P may be phase-shifted fromthe first negative-side RF output signal OS1N by about 180 degrees, andthe second positive-side RF output signal OS2P may be phase-shifted fromthe second negative-side RF output signal OS2N by about 180 degrees.

The output transformer circuitry 20 receives and combines the firstdifferential RF output signal and the second differential RF outputsignal to provide a first transformer output signal TOS1 and a secondtransformer output signal TOS2. In one embodiment of the RF circuitry10, during the first operating mode, the first transformer output signalTOS1 is based on a combination of the first differential RF outputsignal and the second differential RF output signal that substantiallyreinforce one another, and the second transformer output signal TOS2 isbased on a combination of the first differential RF output signal andthe second differential RF output signal that substantially cancel oneanother. As such, the power provided by the first differential RF outputsignal and the power provided by the second differential RF outputsignal may substantially combine to provide the power provided by thefirst transformer output signal TOS1. Since the second transformeroutput signal TOS2 is based on the combination of the first differentialRF output signal and the second differential RF output signal thatsubstantially cancel one another, the power provided by the secondtransformer output signal TOS2 is about zero.

Further, in one embodiment of the RF circuitry 10, during the secondoperating mode, the first transformer output signal TOS1 is based on acombination of the first differential RF output signal and the seconddifferential RF output signal that substantially cancel one another, andthe second transformer output signal TOS2 is based on a combination ofthe first differential RF output signal and the second differential RFoutput signal that substantially reinforce one another. As such, thepower provided by the first differential RF output signal and the powerprovided by the second differential RF output signal may substantiallycombine to provide the power provided by the second transformer outputsignal TOS2. Since the first transformer output signal TOS1 is based onthe combination of the first differential RF output signal and thesecond differential RF output signal that substantially cancel oneanother, the power provided by the first transformer output signal TOS1is about zero.

In one embodiment of the RF circuitry 10 the first transformer outputsignal TOS1 may be a single-ended signal and the second transformeroutput signal TOS2 may be a single-ended signal. In an alternateembodiment of the RF circuitry 10 the first transformer output signalTOS1 may be a differential signal and the second transformer outputsignal TOS2 may be a differential signal. In general, the transformerinput signal TIS is de-multiplexed to provide the first transformeroutput signal TOS1 and the second transformer output signal TOS2 byusing the input switching circuitry 16 to either swap or not swap thedifferential RF switching signals to provide the differential RF inputsignals. By de-multiplexing the transformer input signal TIS to providethe first transformer output signal TOS1 and the second transformeroutput signal TOS2, a single-pole double-throw (1P2T) switch may beeliminated, which would otherwise be needed, thereby reducing insertionloss, cost, space, or any combination thereof. The output transformercircuitry 20 may be used to provide load line transformation between thedifferential RF power amplifier circuitry 18 and downstream circuitry(not shown). Further, the output transformer circuitry 20 may be used toprovide output transistor biasing of the differential RF power amplifiercircuitry 18.

In other embodiments of the RF circuitry 10, the input transformercircuitry 14, the input switching circuitry 16, or both may be replacedwith alternate circuitry. Any or all of the control circuitry 12, theinput transformer circuitry 14, the input switching circuitry 16, thedifferential RF power amplifier circuitry 18, and the output transformercircuitry 20 may be provided by one or more semiconductor die. Further,any or all of the control circuitry 12, the input transformer circuitry14, the input switching circuitry 16, the differential RF poweramplifier circuitry 18, and the output transformer circuitry 20 may beprovided by one or more interconnecting substrate between semiconductordies. The interconnecting substrate may be a laminate.

FIG. 2 shows details of the input transformer circuitry 14, the inputswitching circuitry 16, the differential RF power amplifier circuitry18, and the output transformer circuitry 20 illustrated in FIG. 1according to one embodiment of the input transformer circuitry 14, theinput switching circuitry 16, the differential RF power amplifiercircuitry 18, and the output transformer circuitry 20. The inputtransformer circuitry 14 includes a first input transformer element 22and a second input transformer element 24. The differential RF poweramplifier circuitry 18 includes a first positive-side RF power amplifier26, a first negative-side RF power amplifier 28, a second positive-sideRF power amplifier 30, and a second negative-side RF power amplifier 32.The output transformer circuitry 20 includes a first output transformerelement 34 and a second output transformer element 36.

The first input transformer element 22 includes a first input primaryleg 38 and a first input secondary leg 40. The second input transformerelement 24 includes a second input primary leg 42 and a second inputsecondary leg 44. The first output transformer element 34 includes afirst output primary leg 46, a first output alpha secondary leg 48, anda first output beta secondary leg 50. The second output transformerelement 36 includes a second output primary leg 52, a second outputalpha secondary leg 54, and a second output beta secondary leg 56.

One end of the first input primary leg 38 is coupled to ground and anopposite end of the first input primary leg 38 receives the transformerinput signal TIS. One end of the second input primary leg 42 is coupledto ground and an opposite end of the second input primary leg 42receives the transformer input signal TIS. As such, the transformerinput signal TIS is a single-ended signal and the power provided by thetransformer input signal TIS is split between the first inputtransformer element 22 and the second input transformer element 24. Thefirst input secondary leg 40 provides the first positive-side RFswitching signal SS1P and the first negative-side RF switching signalSS1N. The first input transformer element 22 uses magnetic coupling,electrostatic coupling, or both between the first input primary leg 38and first input secondary leg 40, such that the first input secondaryleg 40 provides the first differential RF switching signal based ontransforming the transformer input signal TIS. The phasing of the firstinput primary leg 38 and first input secondary leg 40 is such that thefirst positive-side RF switching signal SS1P is about phase-aligned withthe transformer input signal TIS.

The second input secondary leg 44 provides the second positive-side RFswitching signal SS2P and the second negative-side RF switching signalSS2N. The second input transformer element 24 uses magnetic coupling,electrostatic coupling, or both between the second input primary leg 42and the second input secondary leg 44, such that the second inputsecondary leg 44 provides the second differential RF switching signalbased on transforming the transformer input signal TIS. The phasing ofthe second input primary leg 42 and the second input secondary leg 44 issuch that the second positive-side RF switching signal SS2P is aboutphase-aligned with the transformer input signal TIS.

The first positive-side RF power amplifier 26 receives and amplifies thefirst positive-side RF input signal IS1P to provide the firstpositive-side RF output signal OS1P. The first negative-side RF poweramplifier 28 receives and amplifies the first negative-side RF inputsignal IS1N to provide the first negative-side RF output signal OS1N.The second positive-side RF power amplifier 30 receives and amplifiesthe second positive-side RF input signal IS2P to provide the secondpositive-side RF output signal OS2P. The second negative-side RF poweramplifier 32 receives and amplifies the second negative-side RF inputsignal IS2N to provide the second negative-side RF output signal OS2N.

The first output primary leg 46 receives the first differential RFoutput signal and the second output primary leg 52 receives the seconddifferential RF output signal. Specifically, one end of the first outputprimary leg 46 receives the first positive-side RF output signal OS1Pand an opposite end of the first output primary leg 46 receives thefirst negative-side RF output signal OS1N. Further, one end of thesecond output primary leg 52 receives the second positive-side RF outputsignal OS2P and an opposite end of the second output primary leg 52receives the second negative-side RF output signal OS2N.

One end of the first output alpha secondary leg 48 provides the firsttransformer output signal TOS1 and an opposite end of the first outputalpha secondary leg 48 is coupled to one end of the second output alphasecondary leg 54. An opposite end of the second output alpha secondaryleg 54 is coupled to ground. Similarly, one end of the first output betasecondary leg 50 provides the second transformer output signal TOS2 andan opposite end of the first output beta secondary leg 50 is coupled toone end of the second output beta secondary leg 56. An opposite end ofthe second output beta secondary leg 56 is coupled to ground. As such,the first output alpha secondary leg 48 and the second output alphasecondary leg 54 are coupled in series to provide the first transformeroutput signal TOS1, and the first output beta secondary leg 50 and thesecond output beta secondary leg 56 are coupled in series to provide thesecond transformer output signal TOS2. Therefore, in this embodiment,the first transformer output signal TOS1 and the second transformeroutput signal TOS2 are single-ended signals.

In this regard, the first output transformer element 34 uses magneticcoupling, electrostatic coupling, or both between the first outputprimary leg 46 and the first output secondary legs 48, 50, such that thefirst output alpha secondary leg 48 provides a portion of the firsttransformer output signal TOS1 based on transforming the firstdifferential RF output signal and the first output beta secondary leg 50provides a portion of the second transformer output signal TOS2 based ontransforming the first differential RF output signal. Further, thesecond output transformer element 36 uses magnetic coupling,electrostatic coupling, or both between the second output primary leg 52and the second output secondary legs 54, 56, such that the second outputalpha secondary leg 54 provides a portion of the first transformeroutput signal TOS1 based on transforming the second differential RFoutput signal and the second output beta secondary leg 56 provides aportion of the second transformer output signal TOS2 based ontransforming a portion of the second differential RF output signal.

Since the first output alpha secondary leg 48 and the second outputalpha secondary leg 54 are coupled in series, the first transformeroutput signal TOS1 is about equal to the portion of the firsttransformer output signal TOS1 provided by the first output alphasecondary leg 48 added to the portion of the first transformer outputsignal TOS1 provided by the second output alpha secondary leg 54. Thephasing of the first output primary leg 46 and the first output alphasecondary leg 48 is such that the portion of the first transformeroutput signal TOS1 provided by the first output alpha secondary leg 48is about phase-aligned with the first positive-side RF output signalOS1P. The phasing of the second output primary leg 52 and the secondoutput alpha secondary leg 54 is such that the portion of the firsttransformer output signal TOS1 provided by the second output alphasecondary leg 54 is about phase-aligned with the second positive-side RFoutput signal OS2P.

Since the first output beta secondary leg 50 and the second output betasecondary leg 56 are coupled in series, the second transformer outputsignal TOS2 is about equal to the portion of the second transformeroutput signal TOS2 provided by the first output beta secondary leg 50added to the portion of the second transformer output signal TOS2provided by the second output beta secondary leg 56. The phasing of thefirst output primary leg 46 and the first output beta secondary leg 50is such that the portion of the second transformer output signal TOS2provided by the first output beta secondary leg 50 is aboutphase-aligned with the first positive-side RF output signal OS1P. Thephasing of the second output primary leg 52 and the second output betasecondary leg 56 is such that the portion of the second transformeroutput signal TOS2 provided by the second output beta secondary leg 56is about phase-aligned with the second negative-side RF output signalOS2N.

FIG. 3 shows details of the RF circuitry 10 illustrated in FIG. 2 duringthe first operating mode of the RF circuitry 10. FIG. 3 includespolarity arrows 58 that show the relative phasing of the first inputprimary leg 38, the first input secondary leg 40, the second inputprimary leg 42, the second input secondary leg 44, the first outputprimary leg 46, the first output alpha secondary leg 48, the firstoutput beta secondary leg 50, the second output primary leg 52, thesecond output alpha secondary leg 54, and the second output betasecondary leg 56. Further, FIG. 3 illustrates forwarding behavior of theinput switching circuitry 16.

During the first operating mode, the input switching circuitry 16 isconfigured, based on the mode select signal MSS, to forward the firstpositive-side RF switching signal SS1P to provide the firstpositive-side RF input signal IS1P, to forward the first negative-sideRF switching signal SS1N to provide the first negative-side RF inputsignal IS1N, to forward the second positive-side RF switching signalSS2P to provide the second positive-side RF input signal IS2P, and toforward the second negative-side RF switching signal SS2N to provide thesecond negative-side RF input signal IS2N.

As illustrated by the polarity arrows 58, the first positive-side RFswitching signal SS1P is about phase-aligned with the transformer inputsignal TIS, and the second positive-side RF switching signal SS2P isabout phase-aligned with the transformer input signal TIS. The firstpositive-side RF input signal IS1P and the first positive-side RF outputsignal OS1P are about phase-aligned with the first positive-side RFswitching signal SS1P. Therefore, the first positive-side RF outputsignal OS1P is about phase-aligned with the transformer input signalTIS. The second positive-side RF input signal IS2P and the secondpositive-side RF output signal OS2P are about phase-aligned with thesecond positive-side RF switching signal SS2P. Therefore, the secondpositive-side RF output signal OS2P is about phase-aligned with thetransformer input signal TIS.

Further, as illustrated by the polarity arrows 58, the portion of thefirst transformer output signal TOS1 provided by the first output alphasecondary leg 48 is about phase-aligned with first positive-side RFoutput signal OS1P, and the portion of the first transformer outputsignal TOS1 provided by the second output alpha secondary leg 54 isabout phase-aligned with the second positive-side RF output signal OS2P.Since both the first positive-side RF output signal OS1P and the secondpositive-side RF output signal OS2P are about phase-aligned with thetransformer input signal TIS, the portion of the first transformeroutput signal TOS1 provided by the first output alpha secondary leg 48is about phase-aligned with the portion of the first transformer outputsignal TOS1 provided by the second output alpha secondary leg 54. As aresult, the powers of the portions of the first transformer outputsignal TOS1 provided by the first output alpha secondary leg 48 and thesecond output alpha secondary leg 54 combine in a reinforcing manner toprovide the first transformer output signal TOS1.

Additionally, as illustrated by the polarity arrows 58, the portion ofthe second transformer output signal TOS2 provided by the first outputbeta secondary leg 50 is about phase-aligned with first positive-side RFoutput signal OS1P, and the portion of the second transformer outputsignal TOS2 provided by the second output beta secondary leg 56 is aboutphase-aligned with the second negative-side RF output signal OS2N. Sinceboth the first positive-side RF output signal OS1P and the secondpositive-side RF output signal OS2P are about phase-aligned with thetransformer input signal TIS, the second negative-side RF output signalOS2N is phase-shifted from the transformer input signal TIS by about 180degrees. As a result, the portion of the second transformer outputsignal TOS2 provided by the first output beta secondary leg 50 isphase-shifted from the portion of the second transformer output signalTOS2 provided by the second output beta secondary leg 56 by about 180degrees. Therefore, the powers of the portions of the second transformeroutput signal TOS2 provided by the first output beta secondary leg 50and the second output beta secondary leg 56 combine in a cancellingmanner to provide the second transformer output signal TOS2, which wouldhave a resulting power about equal to zero.

FIG. 4 shows details of the RF circuitry 10 illustrated in FIG. 2 duringthe second operating mode of the RF circuitry 10. FIG. 4 includes thepolarity arrows 58 that show the relative phasing of the first inputprimary leg 38, the first input secondary leg 40, the second inputprimary leg 42, the second input secondary leg 44, the first outputprimary leg 46, the first output alpha secondary leg 48, the firstoutput beta secondary leg 50, the second output primary leg 52, thesecond output alpha secondary leg 54, and the second output betasecondary leg 56. Further, FIG. 4 illustrates the forwarding behavior ofthe input switching circuitry 16.

During the second operating mode, the input switching circuitry 16 isconfigured, based on the mode select signal MSS, to forward the firstpositive-side RF switching signal SS1P to provide the firstpositive-side RF input signal IS1P, to forward the first negative-sideRF switching signal SS1N to provide the first negative-side RF inputsignal IS1N, to forward the second positive-side RF switching signalSS2P to provide the second negative-side RF input signal IS2N, and toforward the second negative-side RF switching signal SS2N to provide thesecond positive-side RF input signal IS2P.

As illustrated by the polarity arrows 58, the first positive-side RFswitching signal SS1P is about phase-aligned with the transformer inputsignal TIS, and the second positive-side RF switching signal SS2P isabout phase-aligned with the transformer input signal TIS. The firstpositive-side RF input signal IS1P and the first positive-side RF outputsignal OS1P are about phase-aligned with the first positive-side RFswitching signal SS1P. Therefore, the first positive-side RF outputsignal OS1P is about phase-aligned with the transformer input signalTIS. The second negative-side RF input signal IS2N and the secondnegative-side RF output signal OS2N are about phase-aligned with thesecond positive-side RF switching signal SS2P. Therefore, the secondnegative-side RF output signal OS2N is about phase-aligned with thetransformer input signal TIS.

Further, as illustrated by the polarity arrows 58, the portion of thefirst transformer output signal TOS1 provided by the first output alphasecondary leg 48 is about phase-aligned with the first positive-side RFoutput signal OS1P, and the portion of the first transformer outputsignal TOS1 provided by the second output alpha secondary leg 54 isabout phase-aligned with the second negative-side RF output signal OS2N.Since both the first positive-side RF output signal OS1P and the secondnegative-side RF output signal OS2N are about phase-aligned with thetransformer input signal TIS, the portion of the first transformeroutput signal TOS1 provided by the first output alpha secondary leg 48is phase-shifted from the portion of the first transformer output signalTOS1 provided by the second output alpha secondary leg 54 by about 180degrees. As a result, the powers of the portions of the firsttransformer output signal TOS1 provided by the first output alphasecondary leg 48 and the second output alpha secondary leg 54 combine ina cancelling manner to provide the first transformer output signal TOS1,which would have a resulting power equal to about zero.

Additionally, as illustrated by the polarity arrows 58, the portion ofthe second transformer output signal TOS2 provided by the first outputbeta secondary leg 50 is about phase-aligned with first positive-side RFoutput signal OS1P, and the portion of the second transformer outputsignal TOS2 provided by the second output beta secondary leg 56 is aboutphase-aligned with the second negative-side RF output signal OS2N. Sinceboth the first positive-side RF output signal OS1P and the secondnegative-side RF output signal OS2N are about phase-aligned with thetransformer input signal TIS, the portion of the second transformeroutput signal TOS2 provided by the first output beta secondary leg 50 isabout phase-aligned with the portion of the second transformer outputsignal TOS2 provided by the second output beta secondary leg 56.Therefore, the powers of the portions of the second transformer outputsignal TOS2 provided by the first output beta secondary leg 50 and thesecond output beta secondary leg 56 combine in a reinforcing manner toprovide the second transformer output signal TOS2.

FIG. 5 shows the RF circuitry 10 according to an alternate embodiment ofthe RF circuitry 10. The RF circuitry 10 illustrated in FIG. 5 issimilar to the RF circuitry 10 illustrated in FIG. 2, except in the RFcircuitry 10 illustrated in FIG. 5, the control circuitry 12 providesthe mode select signal MSS to both the input switching circuitry 16 andthe differential RF power amplifier circuitry 18. During operation, thecontrol circuitry 12 may select one of multiple operating modes, whichmay include the first operating mode, the second operating mode, and areduced output power operating mode. During the first operating mode,the differential RF power amplifier circuitry 18 provides a first totaloutput power via the first differential RF output signal and the seconddifferential RF output signal based on the mode select signal MSS.During the second operating mode, the differential RF power amplifiercircuitry 18 provides a second total output power via the firstdifferential RF output signal and the second differential RF outputsignal based on the mode select signal MSS. During the reduced outputpower operating mode, the differential RF power amplifier circuitry 18provides a reduced total output power via the first differential RFoutput signal and the second differential RF output signal based on themode select signal MSS. The reduced total output power is less than thefirst total output power and the reduced total output power is less thanthe second total output power.

FIG. 6 shows the RF circuitry 10 according to an additional embodimentof the RF circuitry 10. The RF circuitry 10 illustrated in FIG. 6 issimilar to the RF circuitry 10 illustrated in FIG. 2, except in the RFcircuitry 10 illustrated in FIG. 6, the input transformer circuitry 14further includes a third input transformer element 60 and a fourth inputtransformer element 62; the differential RF power amplifier circuitry 18further includes a third positive-side RF power amplifier 64, a thirdnegative-side RF power amplifier 66, a fourth positive-side RF poweramplifier 68, and a fourth negative-side RF power amplifier 70; and theoutput transformer circuitry 20 further includes a third outputtransformer element 72 and a fourth output transformer element 74.

During operation, the control circuitry 12 may select one of multipleoperating modes, which may include the first operating mode, the secondoperating mode, a third operating mode, and a fourth operating mode. Thecontrol circuitry 12 provides the mode select signal MSS to the inputswitching circuitry 16. The mode select signal MSS may be indicative ofwhich of the multiple operating modes is selected. In general, the modeselect signal MSS is based on which of the multiple operating modes isselected.

The input transformer circuitry 14 receives and splits a transformerinput signal TIS to provide the first differential RF switching signal,the second differential RF switching signal, a third differential RFswitching signal, and a fourth differential RF switching signal to theinput switching circuitry 16. The first differential RF switching signalincludes the first positive-side RF switching signal SS1P and the firstnegative-side RF switching signal SS1N, the second differential RFswitching signal includes the second positive-side RF switching signalSS2P and the second negative-side RF switching signal SS2N, the thirddifferential RF switching signal includes a third positive-side RFswitching signal SS3P and a third negative-side RF switching signalSS3N, and the fourth differential RF switching signal includes a fourthpositive-side RF switching signal SS4P and a fourth negative-side RFswitching signal SS4N. The first positive-side RF switching signal SS1Pmay be phase-shifted about 180 degrees from the first negative-side RFswitching signal SS1N, the second positive-side RF switching signal SS2Pmay be phase-shifted about 180 degrees from the second negative-side RFswitching signal SS2N, the third positive-side RF switching signal SS3Pmay be phase-shifted about 180 degrees from the third negative-side RFswitching signal SS3N, and the fourth positive-side RF switching signalSS4P may be phase-shifted about 180 degrees from the fourthnegative-side RF switching signal SS4N.

In one embodiment of the RF circuitry 10, the transformer input signalTIS is a single-ended signal, as illustrated in FIG. 6. In an alternateembodiment of the RF circuitry 10, which is not shown, the transformerinput signal TIS is a differential signal. The input transformercircuitry 14 may split the power provided by the transformer inputsignal TIS to provide the first differential RF switching signal, thesecond differential RF switching signal, the third differential RFswitching signal, and the fourth differential RF switching signal. Assuch, the power provided by each of the first differential RF switchingsignal, the second differential RF switching signal, the thirddifferential RF switching signal, and the fourth differential RFswitching signal may be about equal to one another. The inputtransformer circuitry 14 may be used to provide load linetransformation.

The input switching circuitry 16 receives and forwards the firstdifferential RF switching signal to provide the first differential RFinput signal based on the mode select signal MSS. The input switchingcircuitry 16 receives and forwards the second differential RF switchingsignal to provide a second differential RF input signal based on themode select signal MSS. The input switching circuitry 16 receives andforwards the third differential RF switching signal to provide a thirddifferential RF input signal based on the mode select signal MSS. Theinput switching circuitry 16 receives and forwards the fourthdifferential RF switching signal to provide a fourth differential RFinput signal based on the mode select signal MSS.

The first differential RF input signal includes the first positive-sideRF input signal IS1P and the first negative-side RF input signal IS1N.The second differential RF input signal includes the secondpositive-side RF input signal IS2P and the second negative-side RF inputsignal IS2N. The third differential RF input signal includes a thirdpositive-side RF input signal IS3P and a third negative-side RF inputsignal IS3N. The fourth differential RF input signal includes a fourthpositive-side RF input signal IS4P and a fourth negative-side RF inputsignal IS4N. The first positive-side RF input signal IS1P may bephase-shifted from the first negative-side RF input signal IS1N by about180 degrees. The second positive-side RF input signal IS2P may bephase-shifted from the second negative-side RF input signal IS2N byabout 180 degrees. The third positive-side RF input signal IS3P may bephase-shifted from the third negative-side RF input signal IS3N by about180 degrees. The fourth positive-side RF input signal IS4P may bephase-shifted from the fourth negative-side RF input signal IS4N byabout 180 degrees.

Depending on the mode select signal MSS, the input switching circuitry16 may receive and forward the first positive-side RF switching signalSS1P to provide the first positive-side RF input signal IS1P, andreceive and forward the first negative-side RF switching signal SS1N toprovide the first negative-side RF input signal IS1N. Alternatively,depending on the mode select signal MSS, the input switching circuitry16 may receive and forward the first positive-side RF switching signalSS1P to provide the first negative-side RF input signal IS1N, andreceive and forward the first negative-side RF switching signal SS1N toprovide the first positive-side RF input signal IS1P.

Depending on the mode select signal MSS, the input switching circuitry16 may receive and forward the second positive-side RF switching signalSS2P to provide the second positive-side RF input signal IS2P, andreceive and forward the second negative-side RF switching signal SS2N toprovide the second negative-side RF input signal IS2N. Alternatively,depending on the mode select signal MSS, the input switching circuitry16 may receive and forward the second positive-side RF switching signalSS2P to provide the second negative-side RF input signal IS2N, andreceive and forward the second negative-side RF switching signal SS2N toprovide the second positive-side RF input signal IS2P.

Depending on the mode select signal MSS, the input switching circuitry16 may receive and forward the third positive-side RF switching signalSS3P to provide the third positive-side RF input signal IS3P, andreceive and forward the third negative-side RF switching signal SS3N toprovide the third negative-side RF input signal IS3N. Alternatively,depending on the mode select signal MSS, the input switching circuitry16 may receive and forward the third positive-side RF switching signalSS3P to provide the third negative-side RF input signal IS3N, andreceive and forward the third negative-side RF switching signal SS3N toprovide the third positive-side RF input signal IS3P.

Depending on the mode select signal MSS, the input switching circuitry16 may receive and forward the fourth positive-side RF switching signalSS4P to provide the fourth positive-side RF input signal IS4P, andreceive and forward the fourth negative-side RF switching signal SS4N toprovide the fourth negative-side RF input signal IS4N. Alternatively,depending on the mode select signal MSS, the input switching circuitry16 may receive and forward the fourth positive-side RF switching signalSS4P to provide the fourth negative-side RF input signal IS4N, andreceive and forward the fourth negative-side RF switching signal SS4N toprovide the fourth positive-side RF input signal IS4P. In general, thefirst differential RF input signal, the second differential RF inputsignal, the third differential RF input signal, and the fourthdifferential RF input signal are based on splitting the transformerinput signal TIS.

In general, the differential RF power amplifier circuitry 18 receivesand amplifies the first differential RF input signal to provide a firstdifferential RF output signal, receives and amplifies the seconddifferential RF input signal to provide a second differential RF outputsignal, receives and amplifies the third differential RF input signal toprovide a third differential RF output signal, and receives andamplifies the fourth differential RF input signal to provide a fourthdifferential RF output signal. The first differential RF output signalincludes the first positive-side RF output signal OS1P and the firstnegative-side RF output signal OS1N, the second differential RF outputsignal includes the second positive-side RF output signal OS2P and thesecond negative-side RF output signal OS2N, the third differential RFoutput signal includes a third positive-side RF output signal OS3P and athird negative-side RF output signal OS3N, and the fourth differentialRF output signal includes a fourth positive-side RF output signal OS4Pand a fourth negative-side RF output signal OS4N. The firstpositive-side RF output signal OS1P may be phase-shifted from the firstnegative-side RF output signal OS1N by about 180 degrees, the secondpositive-side RF output signal OS2P may be phase-shifted from the secondnegative-side RF output signal OS2N by about 180 degrees, the thirdpositive-side RF output signal OS3P may be phase-shifted from the thirdnegative-side RF output signal OS3N by about 180 degrees, and the fourthpositive-side RF output signal OS4P may be phase-shifted from the fourthnegative-side RF output signal OS4N by about 180 degrees.

In the embodiment of the differential RF power amplifier circuitry 18illustrated in FIG. 6, the first positive-side RF power amplifier 26receives and amplifies the first positive-side RF input signal IS1P toprovide the first positive-side RF output signal OS1P. The firstnegative-side RF power amplifier 28 receives and amplifies the firstnegative-side RF input signal IS1N to provide the first negative-side RFoutput signal OS1N. The second positive-side RF power amplifier 30receives and amplifies the second positive-side RF input signal IS2P toprovide the second positive-side RF output signal OS2P. The secondnegative-side RF power amplifier 32 receives and amplifies the secondnegative-side RF input signal IS2N to provide the second negative-sideRF output signal OS2N. The third positive-side RF power amplifier 64receives and amplifies the third positive-side RF input signal IS3P toprovide the third positive-side RF output signal OS3P. The thirdnegative-side RF power amplifier 66 receives and amplifies the thirdnegative-side RF input signal IS3N to provide the third negative-side RFoutput signal OS3N. The fourth positive-side RF power amplifier 68receives and amplifies the fourth positive-side RF input signal IS4P toprovide the fourth positive-side RF output signal OS4P The fourthnegative-side RF power amplifier 70 receives and amplifies the fourthnegative-side RF input signal IS4N to provide the fourth negative-sideRF output signal OS4N.

The output transformer circuitry 20 receives and combines the firstdifferential RF output signal, the second differential RF output signal,the third differential RF output signal, and the fourth differential RFoutput signal to provide the first transformer output signal TOS1, thesecond transformer output signal TOS2, a third transformer output signalTOS3, and a fourth transformer output signal TOS4. In one embodiment ofthe RF circuitry 10, during the first operating mode, the firsttransformer output signal TOS1 is based on a combination of the firstdifferential RF output signal, the second differential RF output signal,the third differential RF output signal, and the fourth differential RFoutput signal that substantially reinforce one another. Additionally,during the first operating mode, the second transformer output signalTOS2 is based on a combination of the first differential RF outputsignal, the second differential RF output signal, the third differentialRF output signal, and the fourth differential RF output signal thatsubstantially cancel one another. Further, during the first operatingmode, the third transformer output signal TOS3 is based on a combinationof the first differential RF output signal, the second differential RFoutput signal, the third differential RF output signal, and the fourthdifferential RF output signal that substantially cancel one another. Inaddition, during the first operating mode, the fourth transformer outputsignal TOS4 is based on a combination of the first differential RFoutput signal, the second differential RF output signal, the thirddifferential RF output signal, and the fourth differential RF outputsignal that substantially cancel one another.

As such, during the first operating mode, the power provided by thefirst differential RF output signal, the power provided by the seconddifferential RF output signal, the power provided by the thirddifferential RF output signal, and the power provided by the fourthdifferential RF output signal may substantially combine to provide thepower provided by the first transformer output signal TOS1. Since thesecond transformer output signal TOS2 is based on the combination of thefirst differential RF output signal, the second differential RF outputsignal, the third differential RF output signal, and the fourthdifferential RF output signal that substantially cancel one another, thepower provided by the second transformer output signal TOS2 is aboutzero. Since the third transformer output signal TOS3 is based on thecombination of the first differential RF output signal, the seconddifferential RF output signal, the third differential RF output signal,and the fourth differential RF output signal that substantially cancelone another, the power provided by the third transformer output signalTOS3 is about zero. Since the fourth transformer output signal TOS4 isbased on the combination of the first differential RF output signal, thesecond differential RF output signal, the third differential RF outputsignal, and the fourth differential RF output signal that substantiallycancel one another, the power provided by the fourth transformer outputsignal TOS4 is about zero.

In one embodiment of the RF circuitry 10, during the second operatingmode, the second transformer output signal TOS2 is based on acombination of the first differential RF output signal, the seconddifferential RF output signal, the third differential RF output signal,and the fourth differential RF output signal that substantiallyreinforce one another. Additionally, during the second operating mode,the first transformer output signal TOS1 is based on a combination ofthe first differential RF output signal, the second differential RFoutput signal, the third differential RF output signal, and the fourthdifferential RF output signal that substantially cancel one another.Further, during the second operating mode, the third transformer outputsignal TOS3 is based on a combination of the first differential RFoutput signal, the second differential RF output signal, the thirddifferential RF output signal, and the fourth differential RF outputsignal that substantially cancel one another. In addition, during thesecond operating mode, the fourth transformer output signal TOS4 isbased on a combination of the first differential RF output signal, thesecond differential RF output signal, the third differential RF outputsignal, and the fourth differential RF output signal that substantiallycancel one another.

As such, during the second operating mode, the power provided by thefirst differential RF output signal, the power provided by the seconddifferential RF output signal, the power provided by the thirddifferential RF output signal, and the power provided by the fourthdifferential RF output signal may substantially combine to provide thepower provided by the second transformer output signal TOS2. Since thefirst transformer output signal TOS1 is based on the combination of thefirst differential RF output signal, the second differential RF outputsignal, the third differential RF output signal, and the fourthdifferential RF output signal that substantially cancel one another, thepower provided by the first transformer output signal TOS1 is aboutzero. Since the third transformer output signal TOS3 is based on thecombination of the first differential RF output signal, the seconddifferential RF output signal, the third differential RF output signal,and the fourth differential RF output signal that substantially cancelone another, the power provided by the third transformer output signalTOS3 is about zero. Since the fourth transformer output signal TOS4 isbased on the combination of the first differential RF output signal, thesecond differential RF output signal, the third differential RF outputsignal, and the fourth differential RF output signal that substantiallycancel one another, the power provided by the fourth transformer outputsignal TOS4 is about zero.

In one embodiment of the RF circuitry 10, during the third operatingmode, the third transformer output signal TOS3 is based on a combinationof the first differential RF output signal, the second differential RFoutput signal, the third differential RF output signal, and the fourthdifferential RF output signal that substantially reinforce one another.Additionally, during the third operating mode, the second transformeroutput signal TOS2 is based on a combination of the first differentialRF output signal, the second differential RF output signal, the thirddifferential RF output signal, and the fourth differential RF outputsignal that substantially cancel one another. Further, during the thirdoperating mode, the first transformer output signal TOS1 is based on acombination of the first differential RF output signal, the seconddifferential RF output signal, the third differential RF output signal,and the fourth differential RF output signal that substantially cancelone another. In addition, during the third operating mode, the fourthtransformer output signal TOS4 is based on a combination of the firstdifferential RF output signal, the second differential RF output signal,the third differential RF output signal, and the fourth differential RFoutput signal that substantially cancel one another.

As such, during the third operating mode, the power provided by thefirst differential RF output signal, the power provided by the seconddifferential RF output signal, the power provided by the thirddifferential RF output signal, and the power provided by the fourthdifferential RF output signal may substantially combine to provide thepower provided by the third transformer output signal TOS3. Since thesecond transformer output signal TOS2 is based on the combination of thefirst differential RF output signal, the second differential RF outputsignal, the third differential RF output signal, and the fourthdifferential RF output signal that substantially cancel one another, thepower provided by the second transformer output signal TOS2 is aboutzero. Since the first transformer output signal TOS1 is based on thecombination of the first differential RF output signal, the seconddifferential RF output signal, the third differential RF output signal,and the fourth differential RF output signal that substantially cancelone another, the power provided by the first transformer output signalTOS1 is about zero. Since the fourth transformer output signal TOS4 isbased on the combination of the first differential RF output signal, thesecond differential RF output signal, the third differential RF outputsignal, and the fourth differential RF output signal that substantiallycancel one another, the power provided by the fourth transformer outputsignal TOS4 is about zero.

In one embodiment of the RF circuitry 10, during the fourth operatingmode, the fourth transformer output signal TOS4 is based on acombination of the first differential RF output signal, the seconddifferential RF output signal, the third differential RF output signal,and the fourth differential RF output signal that substantiallyreinforce one another. Additionally, during the fourth operating mode,the second transformer output signal TOS2 is based on a combination ofthe first differential RF output signal, the second differential RFoutput signal, the third differential RF output signal, and the fourthdifferential RF output signal that substantially cancel one another.Further, during the fourth operating mode, the third transformer outputsignal TOS3 is based on a combination of the first differential RFoutput signal, the second differential RF output signal, the thirddifferential RF output signal, and the fourth differential RF outputsignal that substantially cancel one another. In addition, during thefourth operating mode, the first transformer output signal TOS1 is basedon a combination of the first differential RF output signal, the seconddifferential RF output signal, the third differential RF output signal,and the fourth differential RF output signal that substantially cancelone another.

As such, during the fourth operating mode, the power provided by thefirst differential RF output signal, the power provided by the seconddifferential RF output signal, the power provided by the thirddifferential RF output signal, and the power provided by the fourthdifferential RF output signal may substantially combine to provide thepower provided by the fourth transformer output signal TOS4. Since thesecond transformer output signal TOS2 is based on the combination of thefirst differential RF output signal, the second differential RF outputsignal, the third differential RF output signal, and the fourthdifferential RF output signal that substantially cancel one another, thepower provided by the second transformer output signal TOS2 is aboutzero. Since the third transformer output signal TOS3 is based on thecombination of the first differential RF output signal, the seconddifferential RF output signal, the third differential RF output signal,and the fourth differential RF output signal that substantially cancelone another, the power provided by the third transformer output signalTOS3 is about zero. Since the first transformer output signal TOS1 isbased on the combination of the first differential RF output signal, thesecond differential RF output signal, the third differential RF outputsignal, and the fourth differential RF output signal that substantiallycancel one another, the power provided by the first transformer outputsignal TOS1 is about zero.

In one embodiment of the RF circuitry 10 as shown in FIG. 6, the firsttransformer output signal TOS1 may be a single-ended signal, the secondtransformer output signal TOS2 may be a single-ended signal, the thirddifferential RF output signal may be a single-ended signal, and thefourth differential RF output signal may be a single-ended signal. In analternate embodiment of the RF circuitry 10, which is not shown, thefirst transformer output signal TOS1 may be a differential signal, thesecond transformer output signal TOS2 may be a differential signal, thethird differential RF output signal may be a differential signal, andthe fourth differential RF output signal may be a differential signal.In general, the transformer input signal TIS is de-multiplexed toprovide the first transformer output signal TOS1, the second transformeroutput signal TOS2, the third transformer output signal TOS3, and thefourth transformer output signal TOS4 by using the input switchingcircuitry 16 to either swap or not swap the differential RF switchingsignals to provide the differential RF input signals. By de-multiplexingthe transformer input signal TIS to provide the first transformer outputsignal TOS1, the second transformer output signal TOS2, the thirddifferential RF output signal, and the fourth differential RF outputsignal, a single-pole four-throw (1P4T) switch may be eliminated, whichwould otherwise be needed, thereby reducing insertion loss, cost, space,or any combination thereof. The output transformer circuitry 20 may beused to provide load line transformation between the differential RFpower amplifier circuitry 18 and downstream circuitry (not shown).Further, the output transformer circuitry 20 may be used to provideoutput transistor biasing of the differential RF power amplifiercircuitry 18.

In other embodiments of the RF circuitry 10, the input transformercircuitry 14, the input switching circuitry 16, or both may be replacedwith alternate circuitry. Any or all of the control circuitry 12, theinput transformer circuitry 14, the input switching circuitry 16, thedifferential RF power amplifier circuitry 18, and the output transformercircuitry 20 may be provided by one or more semiconductor die. Further,any or all of the control circuitry 12, the input transformer circuitry14, the input switching circuitry 16, the differential RF poweramplifier circuitry 18, and the output transformer circuitry 20 may beprovided by one or more interconnecting substrate between semiconductordies. The interconnecting substrate may be a laminate.

The first input transformer element 22 includes the first input primaryleg 38 and the first input secondary leg 40. The second inputtransformer element 24 includes the second input primary leg 42 and thesecond input secondary leg 44. The third input transformer element 60includes a third input primary leg 76 and a third input secondary leg78. The fourth input transformer element 62 includes a fourth inputprimary leg 80 and a fourth input secondary leg 82. The first outputtransformer element 34 includes the first output primary leg 46, thefirst output alpha secondary leg 48, the first output beta secondary leg50, a first output gamma secondary leg 84, and a first output deltasecondary leg 86. The second output transformer element 36 includes thesecond output primary leg 52, the second output alpha secondary leg 54,the second output beta secondary leg 56, a second output gamma secondaryleg 88, and a second output delta secondary leg 90. The third outputtransformer element 72 includes a third output primary leg 92, a thirdoutput alpha secondary leg 94, a third output beta secondary leg 96, athird output gamma secondary leg 98, and a third output delta secondaryleg 100. The fourth output transformer element 74 includes a fourthoutput primary leg 102, a fourth output alpha secondary leg 104, afourth output beta secondary leg 106, a fourth output gamma secondaryleg 108, and a fourth output delta secondary leg 110.

One end of the first input primary leg 38 is coupled to ground and anopposite end of the first input primary leg 38 receives the transformerinput signal TIS. One end of the second input primary leg 42 is coupledto ground and an opposite end of the second input primary leg 42receives the transformer input signal TIS. One end of the third inputprimary leg 76 is coupled to ground and an opposite end of the thirdinput primary leg 76 receives the transformer input signal TIS. One endof the fourth input primary leg 80 is coupled to ground and an oppositeend of the fourth input primary leg 80 receives the transformer inputsignal TIS. As such, the transformer input signal TIS is a single-endedsignal and the power provided by the transformer input signal TIS issplit between the first input transformer element 22, the second inputtransformer element 24, the third input transformer element 60, and thefourth input transformer element 62.

The first input secondary leg 40 provides the first positive-side RFswitching signal SS1P and the first negative-side RF switching signalSS1N. The first input transformer element 22 uses magnetic coupling,electrostatic coupling, or both between the first input primary leg 38and first input secondary leg 40, such that the first input secondaryleg 40 provides the first differential RF switching signal based ontransforming the transformer input signal TIS. The phasing of the firstinput primary leg 38 and first input secondary leg 40 is such that thefirst positive-side RF switching signal SS1P is about phase-aligned withthe transformer input signal TIS.

The second input secondary leg 44 provides the second positive-side RFswitching signal SS2P and the second negative-side RF switching signalSS2N. The second input transformer element 24 uses magnetic coupling,electrostatic coupling, or both between the second input primary leg 42and the second input secondary leg 44, such that the second inputsecondary leg 44 provides the second differential RF switching signalbased on transforming the transformer input signal TIS. The phasing ofthe second input primary leg 42 and the second input secondary leg 44 issuch that the second positive-side RF switching signal SS2P is aboutphase-aligned with the transformer input signal TIS.

The third input secondary leg 78 provides the third positive-side RFswitching signal SS3P and the third negative-side RF switching signalSS3N. The third input transformer element 60 uses magnetic coupling,electrostatic coupling, or both between the third input primary leg 76and the third input secondary leg 78, such that the third inputsecondary leg 78 provides the third differential RF switching signalbased on transforming the transformer input signal TIS. The phasing ofthe third input primary leg 76 and the third input secondary leg 78 issuch that the third positive-side RF switching signal SS3P is aboutphase-aligned with the transformer input signal TIS.

The fourth input secondary leg 82 provides the fourth positive-side RFswitching signal SS4P and the fourth negative-side RF switching signalSS4N. The fourth input transformer element 62 uses magnetic coupling,electrostatic coupling, or both between the fourth input primary leg 80and the fourth input secondary leg 82, such that the fourth inputsecondary leg 82 provides the fourth differential RF switching signalbased on transforming the transformer input signal TIS. The phasing ofthe fourth input primary leg 80 and the fourth input secondary leg 82 issuch that the fourth positive-side RF switching signal SS4P is aboutphase-aligned with the transformer input signal TIS.

The first output primary leg 46 receives the first differential RFoutput signal, the second output primary leg 52 receives the seconddifferential RF output signal, the third output primary leg 92 receivesthe third differential RF output signal, and the fourth output primaryleg 102 receives the fourth differential RF output signal. Specifically,one end of the first output primary leg 46 receives the firstpositive-side RF output signal OS1P and an opposite end of the firstoutput primary leg 46 receives the first negative-side RF output signalOS1N. Additionally, one end of the second output primary leg 52 receivesthe second positive-side RF output signal OS2P and an opposite end ofthe second output primary leg 52 receives the second negative-side RFoutput signal OS2N. Further, one end of the third output primary leg 92receives the third positive-side RF output signal OS3P and an oppositeend of the third output primary leg 92 receives the third negative-sideRF output signal OS3N. In addition, one end of the fourth output primaryleg 102 receives the fourth positive-side RF output signal OS4P and anopposite end of the fourth output primary leg 102 receives the fourthnegative-side RF output signal OS4N.

One end of the first output alpha secondary leg 48 provides the firsttransformer output signal TOS1 and an opposite end of the first outputalpha secondary leg 48 is coupled to one end of the second output alphasecondary leg 54. An opposite end of the second output alpha secondaryleg 54 is coupled to one end of the third output alpha secondary leg 94.An opposite end of the third output alpha secondary leg 94 is coupled toone end of the fourth output alpha secondary leg 104. An opposite end ofthe fourth output alpha secondary leg 104 is coupled to ground.Similarly, one end of the first output beta secondary leg 50 providesthe second transformer output signal TOS2 and an opposite end of thefirst output beta secondary leg 50 is coupled to one end of the secondoutput beta secondary leg 56. An opposite end of the second output betasecondary leg 56 is coupled to one end of the third output betasecondary leg 96. An opposite end of the third output beta secondary leg96 is coupled to one end of the fourth output beta secondary leg 106. Anopposite end of the fourth output beta secondary leg 106 is coupled toground.

Further, one end of the first output gamma secondary leg 84 provides thethird transformer output signal TOS3 and an opposite end of the firstoutput gamma secondary leg 84 is coupled to one end of the second outputgamma secondary leg 88. An opposite end of the second output gammasecondary leg 88 is coupled to one end of the third output gammasecondary leg 98 and an opposite end of the third output gamma secondaryleg 98 is coupled to one end of the fourth output gamma secondary leg108. An opposite end of the fourth output gamma secondary leg 108 iscoupled to ground. Additionally, one end of the first output deltasecondary leg 86 provides the fourth transformer output signal TOS4 andan opposite end of the first output delta secondary leg 86 is coupled toone end of the second output delta secondary leg 90. An opposite end ofthe second output delta secondary leg 90 is coupled to one end of thethird output delta secondary leg 100 and an opposite end of the thirdoutput delta secondary leg 100 is coupled to one end of the fourthoutput delta secondary leg 110. An opposite end of the fourth outputdelta secondary leg 110 is coupled to ground.

As a result, the first output alpha secondary leg 48, the second outputalpha secondary leg 54, the third output alpha secondary leg 94, and thefourth output alpha secondary leg 104 are coupled in series to providethe first transformer output signal TOS1. The first output betasecondary leg 50, the second output beta secondary leg 56, the thirdoutput beta secondary leg 96, and the fourth output beta secondary leg106 are coupled in series to provide the second transformer outputsignal TOS2. The first output gamma secondary leg 84, the second outputgamma secondary leg 88, the third output gamma secondary leg 98, and thefourth output gamma secondary leg 108 are coupled in series to providethe third transformer output signal TOS3. The first output deltasecondary leg 86, the second output delta secondary leg 90, the thirdoutput delta secondary leg 100, and the fourth output delta secondaryleg 110 are coupled in series to provide the fourth transformer outputsignal TOS4. Therefore, in this embodiment, the first transformer outputsignal TOS1, the second transformer output signal TOS2, the thirdtransformer output signal TOS3, and the fourth transformer output signalTOS4 are single-ended signals.

In this regard, the first output transformer element 34 uses magneticcoupling, electrostatic coupling, or both between the first outputprimary leg 46 and the first output secondary legs 48, 50, 84, 86, suchthat the first output alpha secondary leg 48 provides a portion of thefirst transformer output signal TOS1 based on transforming the firstdifferential RF output signal, the first output beta secondary leg 50provides a portion of the second transformer output signal TOS2 based ontransforming the first differential RF output signal, the first outputgamma secondary leg 84 provides a portion of the third transformeroutput signal TOS3 based on transforming the first differential RFoutput signal, and the first output delta secondary leg 86 provides aportion of the fourth transformer output signal TOS4 based ontransforming the first differential RF output signal.

Additionally, the second output transformer element 36 uses magneticcoupling, electrostatic coupling, or both between the second outputprimary leg 52 and the second output secondary legs 54, 56, 88, 90, suchthat the second output alpha secondary leg 54 provides a portion of thefirst transformer output signal TOS1 based on transforming the seconddifferential RF output signal, the second output beta secondary leg 56provides a portion of the second transformer output signal TOS2 based ontransforming a portion of the second differential RF output signal, thesecond output gamma secondary leg 88 provides a portion of the thirdtransformer output signal TOS3 based on transforming a portion of thesecond differential RF output signal, and the second output deltasecondary leg 90 provides a portion of the fourth transformer outputsignal TOS4 based on transforming a portion of the second differentialRF output signal.

Further, the third output transformer element 72 uses magnetic coupling,electrostatic coupling, or both between the third output primary leg 92and the third output secondary legs 94, 96, 98, 100, such that the thirdoutput alpha secondary leg 94 provides a portion of the firsttransformer output signal TOS1 based on transforming the thirddifferential RF output signal, the third output beta secondary leg 96provides a portion of the second transformer output signal TOS2 based ontransforming a portion of the third differential RF output signal, thethird output gamma secondary leg 98 provides a portion of the thirdtransformer output signal TOS3 based on transforming a portion of thethird differential RF output signal, and the third output deltasecondary leg 100 provides a portion of the fourth transformer outputsignal TOS4 based on transforming a portion of the third differential RFoutput signal.

In addition, the fourth output transformer element 74 uses magneticcoupling, electrostatic coupling, or both between the fourth outputprimary leg 102 and the fourth output secondary legs 104, 106, 108, 110,such that the fourth output alpha secondary leg 104 provides a portionof the first transformer output signal TOS1 based on transforming thefourth differential RF output signal, the fourth output beta secondaryleg 106 provides a portion of the second transformer output signal TOS2based on transforming a portion of the fourth differential RF outputsignal, the fourth output gamma secondary leg 108 provides a portion ofthe third transformer output signal TOS3 based on transforming a portionof the fourth differential RF output signal, and the fourth output deltasecondary leg 110 provides a portion of the fourth transformer outputsignal TOS4 based on transforming a portion of the fourth differentialRF output signal.

Since the output alpha secondary legs 48, 54, 94, 104 are coupled inseries, the first transformer output signal TOS1 is about equal to theportions of the first transformer output signal TOS1 provided by each ofthe alpha secondary legs 48, 54, 94, 104 added to one another. Thephasing of the first output primary leg 46 and the first output alphasecondary leg 48 is such that the portion of the first transformeroutput signal TOS1 provided by the first output alpha secondary leg 48is about phase-aligned with the first positive-side RF output signalOS1P. The phasing of the second output primary leg 52 and the secondoutput alpha secondary leg 54 is such that the portion of the firsttransformer output signal TOS1 provided by the second output alphasecondary leg 54 is about phase-aligned with the second positive-side RFoutput signal OS2P. The phasing of the third output primary leg 92 andthe third output alpha secondary leg 94 is such that the portion of thefirst transformer output signal TOS1 provided by the third output alphasecondary leg 94 is about phase-aligned with the third positive-side RFoutput signal OS3P. The phasing of the fourth output primary leg 102 andthe fourth output alpha secondary leg 104 is such that the portion ofthe first transformer output signal TOS1 provided by the fourth outputalpha secondary leg 104 is about phase-aligned with the fourthpositive-side RF output signal OS4P.

Since the output beta secondary legs 50, 56, 96, 106 are coupled inseries, the second transformer output signal TOS2 is about equal to theportions of the second transformer output signal TOS2 provided by eachof the beta secondary legs 50, 56, 96, 106 added to one another. Thephasing of the first output primary leg 46 and the first output betasecondary leg 50 is such that the portion of the second transformeroutput signal TOS2 provided by the first output beta secondary leg 50 isabout phase-aligned with the first positive-side RF output signal OS1P.The phasing of the second output primary leg 52 and the second outputbeta secondary leg 56 is such that the portion of the second transformeroutput signal TOS2 provided by the second output beta secondary leg 56is about phase-aligned with the second negative-side RF output signalOS2N. The phasing of the third output primary leg 92 and the thirdoutput beta secondary leg 96 is such that the portion of the secondtransformer output signal TOS2 provided by the third output betasecondary leg 96 is about phase-aligned with the third positive-side RFoutput signal OS3P. The phasing of the fourth output primary leg 102 andthe fourth output beta secondary leg 106 is such that the portion of thesecond transformer output signal TOS2 provided by the fourth output betasecondary leg 106 is about phase-aligned with the fourth positive-sideRF output signal OS4P.

Since the output gamma secondary legs 84, 88, 98, 108 are coupled inseries, the third transformer output signal TOS3 is about equal to theportions of the third transformer output signal TOS3 provided by each ofthe gamma secondary legs 84, 88, 98, 108 added to one another. Thephasing of the first output primary leg 46 and the first output gammasecondary leg 84 is such that the portion of the third transformeroutput signal TOS3 provided by the first output gamma secondary leg 84is about phase-aligned with the first positive-side RF output signalOS1P. The phasing of the second output primary leg 52 and the secondoutput gamma secondary leg 88 is such that the portion of the thirdtransformer output signal TOS3 provided by the second output gammasecondary leg 88 is about phase-aligned with the second positive-side RFoutput signal OS2P. The phasing of the third output primary leg 92 andthe third output gamma secondary leg 98 is such that the portion of thethird transformer output signal TOS3 provided by the third output gammasecondary leg 98 is about phase-aligned with the third negative-side RFoutput signal OS3N. The phasing of the fourth output primary leg 102 andthe fourth output gamma secondary leg 108 is such that the portion ofthe third transformer output signal TOS3 provided by the fourth outputgamma secondary leg 108 is about phase-aligned with the fourthnegative-side RF output signal OS4N.

Since the output delta secondary legs 86, 90, 100, 110 are coupled inseries, the fourth transformer output signal TOS4 is about equal to theportions of the fourth transformer output signal TOS4 provided by eachof the delta secondary legs 86, 90, 100, 110 added to one another. Thephasing of the first output primary leg 46 and the first output deltasecondary leg 86 is such that the portion of the fourth transformeroutput signal TOS4 provided by the first output delta secondary leg 86is about phase-aligned with the first negative-side RF output signalOS1N. The phasing of the second output primary leg 52 and the secondoutput delta secondary leg 90 is such that the portion of the fourthtransformer output signal TOS4 provided by the second output deltasecondary leg 90 is about phase-aligned with the second positive-side RFoutput signal OS2P. The phasing of the third output primary leg 92 andthe third output delta secondary leg 100 is such that the portion of thefourth transformer output signal TOS4 provided by the third output deltasecondary leg 100 is about phase-aligned with the third positive-side RFoutput signal OS3P. The phasing of the fourth output primary leg 102 andthe fourth output delta secondary leg 110 is such that the portion ofthe fourth transformer output signal TOS4 provided by the fourth outputdelta secondary leg 110 is about phase-aligned with the fourthnegative-side RF output signal OS4N.

FIG. 7 shows details of the RF circuitry 10 illustrated in FIG. 6 duringthe first operating mode of the RF circuitry 10. FIG. 7 includes thepolarity arrows 58 that show the relative phasing of the legs 38, 40,42, 44, 46, 48, 50, 52, 54, 56, 76, 78, 80, 82, 84, 86, 88, 90, 92, 94,96, 98, 100, 102, 104, 106, 108, 110. Further, FIG. 7 illustratesforwarding behavior of the input switching circuitry 16.

During the first operating mode, the input switching circuitry 16 isconfigured, based on the mode select signal MSS, to forward the firstpositive-side RF switching signal SS1P to provide the firstpositive-side RF input signal IS1P, to forward the first negative-sideRF switching signal SS1N to provide the first negative-side RF inputsignal IS1N, to forward the second positive-side RF switching signalSS2P to provide the second positive-side RF input signal IS2P, toforward the second negative-side RF switching signal SS2N to provide thesecond negative-side RF input signal IS2N, to forward the thirdpositive-side RF switching signal SS3P to provide the thirdpositive-side RF input signal IS3P, to forward the third negative-sideRF switching signal SS3N to provide the third negative-side RF inputsignal IS3N, to forward the fourth positive-side RF switching signalSS4P to provide the fourth positive-side RF input signal IS4P, and toforward the fourth negative-side RF switching signal SS4N to provide thefourth negative-side RF input signal IS4N.

As illustrated by the polarity arrows 58, the first positive-side RFswitching signal SS1P is about phase-aligned with the transformer inputsignal TIS, the second positive-side RF switching signal SS2P, the thirdpositive-side RF switching signal SS3P, and the fourth positive-side RFswitching signal SS4P are about phase-aligned with the transformer inputsignal TIS. The first positive-side RF input signal IS1P and the firstpositive-side RF output signal OS1P are about phase-aligned with thefirst positive-side RF switching signal SS1P. Therefore, the firstpositive-side RF output signal OS1P is about phase-aligned with thetransformer input signal TIS. The second positive-side RF input signalIS2P and the second positive-side RF output signal OS2P are aboutphase-aligned with the second positive-side RF switching signal SS2P.Therefore, the second positive-side RF output signal OS2P is aboutphase-aligned with the transformer input signal TIS. The thirdpositive-side RF input signal IS3P and the third positive-side RF outputsignal OS3P are about phase-aligned with the third positive-side RFswitching signal SS3P. Therefore, the third positive-side RF outputsignal OS3P is about phase-aligned with the transformer input signalTIS. The fourth positive-side RF input signal IS4P and the fourthpositive-side RF output signal OS4P are about phase-aligned with thefourth positive-side RF switching signal SS4P. Therefore, the fourthpositive-side RF output signal OS4P is about phase-aligned with thetransformer input signal TIS.

In addition, as illustrated by the polarity arrows 58, the portion ofthe first transformer output signal TOS1 provided by the first outputalpha secondary leg 48 is about phase-aligned with first positive-sideRF output signal OS1P, the portion of the first transformer outputsignal TOS1 provided by the second output alpha secondary leg 54 isabout phase-aligned with the second positive-side RF output signal OS2P,the portion of the first transformer output signal TOS1 provided by thethird output alpha secondary leg 94 is about phase-aligned with thethird positive-side RF output signal OS3P, and the portion of the firsttransformer output signal TOS1 provided by the fourth output alphasecondary leg 104 is about phase-aligned with the fourth positive-sideRF output signal OS4P. Since the first positive-side RF output signalOS1P, the second positive-side RF output signal OS2P, the thirdpositive-side RF output signal OS3P, and the fourth positive-side RFoutput signal OS4P are about phase-aligned with the transformer inputsignal TIS, the portion of the first transformer output signal TOS1provided by each of the output alpha secondary legs 48, 54, 94, 104 areabout phase-aligned with one another. As a result, the powers of theportions of the first transformer output signal TOS1 provided by theoutput alpha secondary legs 48, 54, 94, 104 combine in a reinforcingmanner to provide the first transformer output signal TOS1.

Further, as illustrated by the polarity arrows 58, the portion of thesecond transformer output signal TOS2 provided by the first output betasecondary leg 50 is about phase-aligned with first positive-side RFoutput signal OS1P, the portion of the second transformer output signalTOS2 provided by the second output beta secondary leg 56 is aboutphase-aligned with the second negative-side RF output signal OS2N, theportion of the second transformer output signal TOS2 provided by thethird output beta secondary leg 96 is about phase-aligned with thirdpositive-side RF output signal OS3P, and the portion of the secondtransformer output signal TOS2 provided by the fourth output betasecondary leg 106 is about phase-aligned with the fourth negative-sideRF output signal OS4N. Since half of the first positive-side RF outputsignal OS1P, the second negative-side RF output signal OS2N, the thirdpositive-side RF output signal OS3P, and the fourth negative-side RFoutput signal OS4N are about phase-aligned with the transformer inputsignal TIS and the other half are phase-shifted about 180 degrees fromthe transformer input signal TIS, the portion of the second transformeroutput signal TOS2 provided by each of the output beta secondary legs50, 56, 96, 106 approximately cancel one another. As a result, thepowers of the portions of the second transformer output signal TOS2provided by the output beta secondary legs 50, 56, 96, 106 combine in acancelling manner to provide the second transformer output signal TOS2,which would have a resulting power about equal to zero.

Additionally, as illustrated by the polarity arrows 58, the portion ofthe third transformer output signal TOS3 provided by the first outputgamma secondary leg 84 is about phase-aligned with first positive-sideRF output signal OS1P, the portion of the third transformer outputsignal TOS3 provided by the second output gamma secondary leg 88 isabout phase-aligned with the second positive-side RF output signal OS2P,the portion of the third transformer output signal TOS3 provided by thethird output gamma secondary leg 98 is about phase-aligned with thirdnegative-side RF output signal OS3N, and the portion of the thirdtransformer output signal TOS3 provided by the fourth output gammasecondary leg 108 is about phase-aligned with the fourth negative-sideRF output signal OS4N. Since half of the first positive-side RF outputsignal OS1P, the second positive-side RF output signal OS2P, the thirdnegative-side RF output signal OS3N, and the fourth negative-side RFoutput signal OS4N are about phase-aligned with the transformer inputsignal TIS and the other half are phase-shifted about 180 degrees fromthe transformer input signal TIS, the portion of the third transformeroutput signal TOS3 provided by each of the output gamma secondary legs84, 88, 98, 108 approximately cancel one another. As a result, thepowers of the portions of the third transformer output signal TOS3provided by the output gamma secondary legs 84, 88, 98, 108 combine in acancelling manner to provide the third transformer output signal TOS3,which would have a resulting power about equal to zero.

Furthermore, as illustrated by the polarity arrows 58, the portion ofthe fourth transformer output signal TOS4 provided by the first outputdelta secondary leg 86 is about phase-aligned with the firstnegative-side RF output signal OS1N, the portion of the fourthtransformer output signal TOS4 provided by the second output deltasecondary leg 90 is about phase-aligned with the second positive-side RFoutput signal OS2P, the portion of the fourth transformer output signalTOS4 provided by the third output delta secondary leg 100 is aboutphase-aligned with the third positive-side RF output signal OS3P, andthe portion of the fourth transformer output signal TOS4 provided by thefourth output delta secondary leg 110 is about phase-aligned with thefourth negative-side RF output signal OS4N. Since half of the firstnegative-side RF output signal OS1N, the second positive-side RF outputsignal OS2P, the third positive-side RF output signal OS3P, and thefourth negative-side RF output signal OS4N are about phase-aligned withthe transformer input signal TIS and the other half are phase-shiftedabout 180 degrees from the transformer input signal TIS, the portion ofthe fourth transformer output signal TOS4 provided by each of the outputdelta secondary legs 86, 90, 100, 110 approximately cancel one another.As a result, the powers of the portions of the fourth transformer outputsignal TOS4 provided by the output delta secondary legs 86, 90 100, 110combine in a cancelling manner to provide the fourth transformer outputsignal TOS4, which would have a resulting power about equal to zero.

FIG. 8 shows details of the RF circuitry 10 illustrated in FIG. 6 duringthe second operating mode of the RF circuitry 10. FIG. 8 includes thepolarity arrows 58 that show the relative phasing of the legs 38, 40,42, 44, 46, 48, 50, 52, 54, 56, 76, 78, 80, 82, 84, 86, 88, 90, 92, 94,96, 98, 100, 102, 104, 106, 108, 110. Further, FIG. 8 illustratesforwarding behavior of the input switching circuitry 16.

During the second operating mode, the input switching circuitry 16 isconfigured, based on the mode select signal MSS, to forward the firstpositive-side RF switching signal SS1P to provide the firstpositive-side RF input signal IS1P, to forward the first negative-sideRF switching signal SS1N to provide the first negative-side RF inputsignal IS1N, to forward the second positive-side RF switching signalSS2P to provide the second negative-side RF input signal IS2N, toforward the second negative-side RF switching signal SS2N to provide thesecond positive-side RF input signal IS2P, to forward the thirdpositive-side RF switching signal SS3P to provide the thirdpositive-side RF input signal 153P, to forward the third negative-sideRF switching signal SS3N to provide the third negative-side RF inputsignal 153N, to forward the fourth positive-side RF switching signalSS4P to provide the fourth negative-side RF input signal 154N, and toforward the fourth negative-side RF switching signal SS4N to provide thefourth positive-side RF input signal IS4P.

As illustrated by the polarity arrows 58, the first positive-side RFswitching signal SS1P is about phase-aligned with the transformer inputsignal TIS, the second positive-side RF switching signal SS2P, the thirdpositive-side RF switching signal SS3P, and the fourth positive-side RFswitching signal SS4P are about phase-aligned with the transformer inputsignal TIS. The first positive-side RF input signal IS1P and the firstpositive-side RF output signal OS1P are about phase-aligned with thefirst positive-side RF switching signal SS1P. Therefore, the firstpositive-side RF output signal OS1P is about phase-aligned with thetransformer input signal TIS. The second positive-side RF input signalIS2P and the second positive-side RF output signal OS2P are aboutphase-aligned with the second negative-side RF switching signal SS2N.Therefore, the second negative-side RF output signal OS2N is aboutphase-aligned with the transformer input signal TIS. The thirdpositive-side RF input signal IS3P and the third positive-side RF outputsignal OS3P are about phase-aligned with the third positive-side RFswitching signal SS3P. Therefore, the third positive-side RF outputsignal OS3P is about phase-aligned with the transformer input signalTIS. The fourth positive-side RF input signal IS4P and the fourthpositive-side RF output signal OS4P are about phase-aligned with thefourth negative-side RF switching signal SS4N. Therefore, the fourthnegative-side RF output signal OS4N is about phase-aligned with thetransformer input signal TIS.

In addition, as illustrated by the polarity arrows 58, the portion ofthe first transformer output signal TOS1 provided by the first outputalpha secondary leg 48 is about phase-aligned with first positive-sideRF output signal OS1P, the portion of the first transformer outputsignal TOS1 provided by the second output alpha secondary leg 54 isabout phase-aligned with the second negative-side RF output signal OS2N,the portion of the first transformer output signal TOS1 provided by thethird output alpha secondary leg 94 is about phase-aligned with thirdpositive-side RF output signal OS3P, and the portion of the firsttransformer output signal TOS1 provided by the fourth output alphasecondary leg 104 is about phase-aligned with fourth negative-side RFoutput signal OS4N. Since half of the first positive-side RF outputsignal OS1P, the second negative-side RF output signal OS2N, the thirdpositive-side RF output signal OS3P, and the fourth negative-side RFoutput signal OS4N are about phase-aligned with the transformer inputsignal TIS and the other half are phase-shifted about 180 degrees fromthe transformer input signal TIS, the portion of the first transformeroutput signal TOS1 provided by each of the output alpha secondary legs48, 54, 94, 104 approximately cancel one another. As a result, thepowers of the portions of the first transformer output signal TOS1provided by the output alpha secondary legs 48, 54, 94, 104 combine in acancelling manner to provide the first transformer output signal TOS1,which would have a resulting power about equal to zero.

Further, as illustrated by the polarity arrows 58, the portion of thesecond transformer output signal TOS2 provided by the first output betasecondary leg 50 is about phase-aligned with first positive-side RFoutput signal OS1P, the portion of the second transformer output signalTOS2 provided by the second output beta secondary leg 56 is aboutphase-aligned with the second positive-side RF output signal OS2P, theportion of the second transformer output signal TOS2 provided by thethird output beta secondary leg 96 is about phase-aligned with thirdpositive-side RF output signal OS3P, and the portion of the secondtransformer output signal TOS2 provided by the fourth output betasecondary leg 106 is about phase-aligned with the fourth positive-sideRF output signal OS4P. Since the first positive-side RF output signalOS1P, the second positive-side RF output signal OS2P, the thirdpositive-side RF output signal OS3P, and the fourth positive-side RFoutput signal OS4P are about phase-aligned with the transformer inputsignal TIS, the portion of the second transformer output signal TOS2provided by each of the output beta secondary legs 50, 56, 96, 106 areabout phase-aligned with one another. As a result, the powers of theportions of the second transformer output signal TOS2 provided by theoutput beta secondary legs 50, 56, 96, 106 combine in a reinforcingmanner to provide the second transformer output signal TOS2.

Additionally, as illustrated by the polarity arrows 58, the portion ofthe third transformer output signal TOS3 provided by the first outputgamma secondary leg 84 is about phase-aligned with first positive-sideRF output signal OS1P, the portion of the third transformer outputsignal TOS3 provided by the second output gamma secondary leg 88 isabout phase-aligned with the second negative-side RF output signal OS2N,the portion of the third transformer output signal TOS3 provided by thethird output gamma secondary leg 98 is about phase-aligned with thirdnegative-side RF output signal OS3N, and the portion of the thirdtransformer output signal TOS3 provided by the fourth output gammasecondary leg 108 is about phase-aligned with fourth positive-side RFoutput signal OS4P. Since half of the first positive-side RF outputsignal OS1P, the second negative-side RF output signal OS2N, the thirdnegative-side RF output signal OS3N, and the fourth positive-side RFoutput signal OS4P are about phase-aligned with the transformer inputsignal TIS and the other half are phase-shifted about 180 degrees fromthe transformer input signal TIS, the portion of the third transformeroutput signal TOS3 provided by each of the output gamma secondary legs84, 88, 98, 108 approximately cancel one another. As a result, thepowers of the portions of the third transformer output signal TOS3provided by the output gamma secondary legs 84, 88, 98, 108 combine in acancelling manner to provide the third transformer output signal TOS3,which would have a resulting power about equal to zero.

Furthermore, as illustrated by the polarity arrows 58, the portion ofthe fourth transformer output signal TOS4 provided by the first outputdelta secondary leg 86 is about phase-aligned with the firstnegative-side RF output signal OS1N, the portion of the fourthtransformer output signal TOS4 provided by the second output deltasecondary leg 90 is about phase-aligned with the second negative-side RFoutput signal OS2N, the portion of the fourth transformer output signalTOS4 provided by the third output delta secondary leg 100 is aboutphase-aligned with the third positive-side RF output signal OS3P, andthe portion of the fourth transformer output signal TOS4 provided by thefourth output delta secondary leg 110 is about phase-aligned with thefourth positive-side RF output signal OS4P. Since half of the firstnegative-side RF output signal OS1N, the second negative-side RF outputsignal OS2N, the third positive-side RF output signal OS3P, and thefourth positive-side RF output signal OS4P are about phase-aligned withthe transformer input signal TIS and the other half are phase-shiftedabout 180 degrees from the transformer input signal TIS, the portion ofthe fourth transformer output signal TOS4 provided by each of the outputdelta secondary legs 86, 90, 100, 110 approximately cancel one another.As a result, the powers of the portions of the fourth transformer outputsignal TOS4 provided by the output delta secondary legs 86, 90 100, 110combine in a cancelling manner to provide the fourth transformer outputsignal TOS4, which would have a resulting power about equal to zero.

FIG. 9 shows details of the RF circuitry 10 illustrated in FIG. 6 duringthe third operating mode of the RF circuitry 10. FIG. 9 includes thepolarity arrows 58 that show the relative phasing of the legs 38, 40,42, 44, 46, 48, 50, 52, 54, 56, 76, 78, 80, 82, 84, 86, 88, 90, 92, 94,96, 98, 100, 102, 104, 106, 108, 110. Further, FIG. 9 illustratesforwarding behavior of the input switching circuitry 16.

During the third operating mode, the input switching circuitry 16 isconfigured, based on the mode select signal MSS, to forward the firstpositive-side RF switching signal SS1P to provide the firstpositive-side RF input signal IS1P, to forward the first negative-sideRF switching signal SS1N to provide the first negative-side RF inputsignal IS1N, to forward the second positive-side RF switching signalSS2P to provide the second positive-side RF input signal IS2P, toforward the second negative-side RF switching signal SS2N to provide thesecond negative-side RF input signal IS2N, to forward the thirdpositive-side RF switching signal SS3P to provide the thirdnegative-side RF input signal IS3N, to forward the third negative-sideRF switching signal SS3N to provide the third positive-side RF inputsignal IS3P, to forward the fourth positive-side RF switching signalSS4P to provide the fourth negative-side RF input signal IS4N, and toforward the fourth negative-side RF switching signal SS4N to provide thefourth positive-side RF input signal IS4P.

As illustrated by the polarity arrows 58, the first positive-side RFswitching signal SS1P is about phase-aligned with the transformer inputsignal TIS, the second positive-side RF switching signal SS2P, the thirdpositive-side RF switching signal SS3P, and the fourth positive-side RFswitching signal SS4P are about phase-aligned with the transformer inputsignal TIS. The first positive-side RF input signal IS1P and the firstpositive-side RF output signal OS1P are about phase-aligned with thefirst positive-side RF switching signal SS1P. Therefore, the firstpositive-side RF output signal OS1P is about phase-aligned with thetransformer input signal TIS. The second positive-side RF input signalIS2P and the second positive-side RF output signal OS2P are aboutphase-aligned with the second positive-side RF switching signal SS2P.Therefore, the second positive-side RF output signal OS2P is aboutphase-aligned with the transformer input signal TIS. The thirdpositive-side RF input signal IS3P and the third positive-side RF outputsignal OS3P are about phase-aligned with the third negative-side RFswitching signal SS3N. Therefore, the third negative-side RF outputsignal OS3N is about phase-aligned with the transformer input signalTIS. The fourth positive-side RF input signal IS4P and the fourthpositive-side RF output signal OS4P are about phase-aligned with thefourth negative-side RF switching signal SS4N. Therefore, the fourthnegative-side RF output signal OS4N is about phase-aligned with thetransformer input signal TIS.

In addition, as illustrated by the polarity arrows 58, the portion ofthe first transformer output signal TOS1 provided by the first outputalpha secondary leg 48 is about phase-aligned with first positive-sideRF output signal OS1P, the portion of the first transformer outputsignal TOS1 provided by the second output alpha secondary leg 54 isabout phase-aligned with the second positive-side RF output signal OS2P,the portion of the first transformer output signal TOS1 provided by thethird output alpha secondary leg 94 is about phase-aligned with thirdnegative-side RF output signal OS3N, and the portion of the firsttransformer output signal TOS1 provided by the fourth output alphasecondary leg 104 is about phase-aligned with fourth negative-side RFoutput signal OS4N. Since half of the first positive-side RF outputsignal OS1P, the second positive-side RF output signal OS2P, the thirdnegative-side RF output signal OS3N, and the fourth negative-side RFoutput signal OS4N are about phase-aligned with the transformer inputsignal TIS and the other half are phase-shifted about 180 degrees fromthe transformer input signal TIS, the portion of the first transformeroutput signal TOS1 provided by each of the output alpha secondary legs48, 54, 94, 104 approximately cancel one another. As a result, thepowers of the portions of the first transformer output signal TOS1provided by the output alpha secondary legs 48, 54, 94, 104 combine in acancelling manner to provide the first transformer output signal TOS1,which would have a resulting power about equal to zero.

Further, as illustrated by the polarity arrows 58, the portion of thesecond transformer output signal TOS2 provided by the first output betasecondary leg 50 is about phase-aligned with the first positive-side RFoutput signal OS1P, the portion of the second transformer output signalTOS2 provided by the second output beta secondary leg 56 is aboutphase-aligned with the second negative-side RF output signal OS2N, theportion of the second transformer output signal TOS2 provided by thethird output beta secondary leg 96 is about phase-aligned with the thirdnegative-side RF output signal OS3N, and the portion of the secondtransformer output signal TOS2 provided by the fourth output betasecondary leg 106 is about phase-aligned with the fourth positive-sideRF output signal OS4P. Since half of the first positive-side RF outputsignal OS1P, the second negative-side RF output signal OS2N, the thirdnegative-side RF output signal OS3N, and the fourth positive-side RFoutput signal OS4P are about phase-aligned with the transformer inputsignal TIS and the other half are phase-shifted about 180 degrees fromthe transformer input signal TIS, the portion of the second transformeroutput signal TOS2 provided by each of the output beta secondary legs50, 56, 96, 106 approximately cancel one another. As a result, thepowers of the portions of the second transformer output signal TOS2provided by the output beta secondary legs 50, 56, 96, 106 combine in acancelling manner to provide the second transformer output signal TOS2,which would have a resulting power about equal to zero.

Additionally, as illustrated by the polarity arrows 58, the portion ofthe third transformer output signal TOS3 provided by the first outputgamma secondary leg 84 is about phase-aligned with the firstpositive-side RF output signal OS1P, the portion of the thirdtransformer output signal TOS3 provided by the second output gammasecondary leg 88 is about phase-aligned with the second positive-side RFoutput signal OS2P, the portion of the third transformer output signalTOS3 provided by the third output gamma secondary leg 98 is aboutphase-aligned with the third positive-side RF output signal OS3P, andthe portion of the third transformer output signal TOS3 provided by thefourth output gamma secondary leg 108 is about phase-aligned with thefourth positive-side RF output signal OS4P. Since the firstpositive-side RF output signal OS1P, the second positive-side RF outputsignal OS2P, the third positive-side RF output signal OS3P, and thefourth positive-side RF output signal OS4P are about phase-aligned withthe transformer input signal TIS, the portion of the third transformeroutput signal TOS3 provided by each of the output gamma secondary legs84, 88, 98, 108 are about phase-aligned with one another. As a result,the powers of the portions of the third transformer output signal TOS3provided by the output gamma secondary legs 84, 88, 98, 108 combine in areinforcing manner to provide the third transformer output signal TOS3.

Furthermore, as illustrated by the polarity arrows 58, the portion ofthe fourth transformer output signal TOS4 provided by the first outputdelta secondary leg 86 is about phase-aligned with first negative-sideRF output signal OS1N, the portion of the fourth transformer outputsignal TOS4 provided by the second output delta secondary leg 90 isabout phase-aligned with the second positive-side RF output signal OS2P,the portion of the fourth transformer output signal TOS4 provided by thethird output delta secondary leg 100 is about phase-aligned with thirdnegative-side RF output signal OS3N, and the portion of the fourthtransformer output signal TOS4 provided by the fourth output deltasecondary leg 110 is about phase-aligned with the fourth positive-sideRF output signal OS4P. Since half of the first negative-side RF outputsignal OS1N, the second positive-side RF output signal OS2P, the thirdnegative-side RF output signal OS3N, and the fourth positive-side RFoutput signal OS4P are about phase-aligned with the transformer inputsignal TIS and the other half are phase-shifted about 180 degrees fromthe transformer input signal TIS, the portion of the fourth transformeroutput signal TOS4 provided by each of the output delta secondary legs86, 90, 100, 110 approximately cancel one another. As a result, thepowers of the portions of the fourth transformer output signal TOS4provided by the output delta secondary legs 86, 90 100, 110 combine in acancelling manner to provide the fourth transformer output signal TOS4,which would have a resulting power about equal to zero.

FIG. 10 shows details of the RF circuitry 10 illustrated in FIG. 6during the fourth operating mode of the RF circuitry 10. FIG. 10includes the polarity arrows 58 that show the relative phasing of thelegs 38, 40, 42, 44, 46, 48, 50, 52, 54, 56, 76, 78, 80, 82, 84, 86, 88,90, 92, 94, 96, 98, 100, 102, 104, 106, 108, 110. Further, FIG. 10illustrates forwarding behavior of the input switching circuitry 16.

During the fourth operating mode, the input switching circuitry 16 isconfigured, based on the mode select signal MSS, to forward the firstpositive-side RF switching signal SS1P to provide the firstnegative-side RF input signal IS1N, to forward the first negative-sideRF switching signal SS1N to provide the first positive-side RF inputsignal IS1P, to forward the second positive-side RF switching signalSS2P to provide the second positive-side RF input signal IS2P, toforward the second negative-side RF switching signal SS2N to provide thesecond negative-side RF input signal IS2N, to forward the thirdpositive-side RF switching signal SS3P to provide the thirdpositive-side RF input signal IS3P, to forward the third negative-sideRF switching signal SS3N to provide the third negative-side RF inputsignal IS3N, to forward the fourth positive-side RF switching signalSS4P to provide the fourth negative-side RF input signal IS4N, and toforward the fourth negative-side RF switching signal SS4N to provide thefourth positive-side RF input signal IS4P.

As illustrated by the polarity arrows 58, the first positive-side RFswitching signal SS1P is about phase-aligned with the transformer inputsignal TIS, the second positive-side RF switching signal SS2P, the thirdpositive-side RF switching signal SS3P, and the fourth positive-side RFswitching signal SS4P are about phase-aligned with the transformer inputsignal TIS. The first positive-side RF input signal IS1P and the firstpositive-side RF output signal OS1P are about phase-aligned with thefirst negative-side RF switching signal SS1N. Therefore, the firstnegative-side RF output signal OS1N is about phase-aligned with thetransformer input signal TIS. The second positive-side RF input signalIS2P and the second positive-side RF output signal OS2P are aboutphase-aligned with the second positive-side RF switching signal SS2P.Therefore, the second positive-side RF output signal OS2P is aboutphase-aligned with the transformer input signal TIS. The thirdpositive-side RF input signal IS3P and the third positive-side RF outputsignal OS3P are about phase-aligned with the third positive-side RFswitching signal SS3P. Therefore, the third positive-side RF outputsignal OS3P is about phase-aligned with the transformer input signalTIS. The fourth positive-side RF input signal IS4P and the fourthpositive-side RF output signal OS4P are about phase-aligned with thefourth negative-side RF switching signal SS4N. Therefore, the fourthnegative-side RF output signal OS4N is about phase-aligned with thetransformer input signal TIS.

In addition, as illustrated by the polarity arrows 58, the portion ofthe first transformer output signal TOS1 provided by the first outputalpha secondary leg 48 is about phase-aligned with the firstnegative-side RF output signal OS1N, the portion of the firsttransformer output signal TOS1 provided by the second output alphasecondary leg 54 is about phase-aligned with the second positive-side RFoutput signal OS2P, the portion of the first transformer output signalTOS1 provided by the third output alpha secondary leg 94 is aboutphase-aligned with the third positive-side RF output signal OS3P, andthe portion of the first transformer output signal TOS1 provided by thefourth output alpha secondary leg 104 is about phase-aligned with fourthnegative-side RF output signal OS4N. Since half of the firstnegative-side RF output signal OS1N, the second positive-side RF outputsignal OS2P, the third positive-side RF output signal OS3P, and thefourth negative-side RF output signal OS4N are about phase-aligned withthe transformer input signal TIS and the other half are phase-shiftedabout 180 degrees from the transformer input signal TIS, the portion ofthe first transformer output signal TOS1 provided by each of the outputalpha secondary legs 48, 54, 94, 104 approximately cancel one another.As a result, the powers of the portions of the first transformer outputsignal TOS1 provided by the output alpha secondary legs 48, 54, 94, 104combine in a cancelling manner to provide the first transformer outputsignal TOS1, which would have a resulting power about equal to zero.

Further, as illustrated by the polarity arrows 58, the portion of thesecond transformer output signal TOS2 provided by the first output betasecondary leg 50 is about phase-aligned with the first negative-side RFoutput signal OS1N, the portion of the second transformer output signalTOS2 provided by the second output beta secondary leg 56 is aboutphase-aligned with the second negative-side RF output signal OS2N, theportion of the second transformer output signal TOS2 provided by thethird output beta secondary leg 96 is about phase-aligned with the thirdpositive-side RF output signal OS3P, and the portion of the secondtransformer output signal TOS2 provided by the fourth output betasecondary leg 106 is about phase-aligned with the fourth positive-sideRF output signal OS4P. Since half of the first negative-side RF outputsignal OS1N, the second negative-side RF output signal OS2N, the thirdpositive-side RF output signal OS3P, and the fourth positive-side RFoutput signal OS4P are about phase-aligned with the transformer inputsignal TIS and the other half are phase-shifted about 180 degrees fromthe transformer input signal TIS, the portion of the second transformeroutput signal TOS2 provided by each of the output beta secondary legs50, 56, 96, 106 approximately cancel one another. As a result, thepowers of the portions of the second transformer output signal TOS2provided by the output beta secondary legs 50, 56, 96, 106 combine in acancelling manner to provide the second transformer output signal TOS2,which would have a resulting power about equal to zero.

Additionally, as illustrated by the polarity arrows 58, the portion ofthe third transformer output signal TOS3 provided by the first outputgamma secondary leg 84 is about phase-aligned with the firstnegative-side RF output signal OS1N, the portion of the thirdtransformer output signal TOS3 provided by the second output gammasecondary leg 88 is about phase-aligned with the second negative-side RFoutput signal OS2N, the portion of the third transformer output signalTOS3 provided by the third output gamma secondary leg 98 is aboutphase-aligned with the third positive-side RF output signal OS3P, andthe portion of the third transformer output signal TOS3 provided by thefourth output gamma secondary leg 108 is about phase-aligned with thefourth positive-side RF output signal OS4P. Since half of the firstnegative-side RF output signal OS1N, the second negative-side RF outputsignal OS2N, the third positive-side RF output signal OS3P, and thefourth positive-side RF output signal OS4P are about phase-aligned withthe transformer input signal TIS and the other half are phase-shiftedabout 180 degrees from the transformer input signal TIS, the portion ofthe third transformer output signal TOS3 provided by each of the outputgamma secondary legs 84, 88, 98, 108 approximately cancel one another.As a result, the powers of the portions of the third transformer outputsignal TOS3 provided by the output gamma secondary legs 84, 88, 98, 108combine in a cancelling manner to provide the third transformer outputsignal TOS3, which would have a resulting power about equal to zero.

Furthermore, as illustrated by the polarity arrows 58, the portion ofthe fourth transformer output signal TOS4 provided by the first outputdelta secondary leg 86 is about phase-aligned with first positive-sideRF output signal OS1P, the portion of the fourth transformer outputsignal TOS4 provided by the second output delta secondary leg 90 isabout phase-aligned with the second positive-side RF output signal OS2P,the portion of the fourth transformer output signal TOS4 provided by thethird output delta secondary leg 100 is about phase-aligned with thirdpositive-side RF output signal OS3P, and the portion of the fourthtransformer output signal TOS4 provided by the fourth output deltasecondary leg 110 is about phase-aligned with fourth positive-side RFoutput signal OS4P. Since the first positive-side RF output signal OS1P,the second positive-side RF output signal OS2P, the third positive-sideRF output signal OS3P, and the fourth positive-side RF output signalOS4P are about phase-aligned with the transformer input signal TIS, theportion of the fourth transformer output signal TOS4 provided by each ofthe output delta secondary legs 86, 90, 100, 110 are about phase-alignedwith one another. As a result, the powers of the portions of the fourthtransformer output signal TOS4 provided by the output delta secondarylegs 86, 90, 100, 110 combine in a reinforcing manner to provide thefourth transformer output signal TOS4.

FIG. 11 shows the RF circuitry 10 according to another embodiment of theRF circuitry 10. The RF circuitry 10 illustrated in FIG. 11 is similarto the RF circuitry 10 illustrated in FIG. 2. During operation, thecontrol circuitry 12 may select one of multiple operating modes, whichmay include the first operating mode, the second operating mode, and upto and including a K^(TH) operating mode. The control circuitry 12provides a mode select signal MSS to the input switching circuitry 16.The mode select signal MSS may be indicative of which of the multipleoperating modes is selected. In general, the mode select signal MSS isbased on which of the multiple operating modes is selected.

The input transformer circuitry 14 receives and splits a transformerinput signal TIS to provide the first differential RF switching signal,the second differential RF switching signal, and up to and including anM^(TH) differential RF switching signal to the input switching circuitry16. The first differential RF switching signal includes a firstpositive-side RF switching signal SS1P and a first negative-side RFswitching signal SS1N. The second differential RF switching signalincludes a second positive-side RF switching signal SS2P and a secondnegative-side RF switching signal SS2N. The M^(TH) differential RFswitching signal includes an M^(TH) positive-side RF switching signalSSMP and an M^(TH) negative-side RF switching signal SSMN.

The first positive-side RF switching signal SS1P may be phase-shiftedabout 180 degrees from the first negative-side RF switching signal SS1N,the second positive-side RF switching signal SS2P may be phase-shiftedabout 180 degrees from the second negative-side RF switching signal SS2Nand the M^(TH) positive-side RF switching signal SSMP may bephase-shifted about 180 degrees from the M^(TH) negative-side RFswitching signal SSMN. In one embodiment of the RF circuitry 10, thetransformer input signal TIS is a single-ended signal. In an alternateembodiment of the RF circuitry 10, the transformer input signal TIS is adifferential signal. The input transformer circuitry 14 may split thepower provided by the transformer input signal TIS to provide thedifferential RF switching signals. As such, the power provided by eachof the differential RF switching signals may be about equal to oneanother. The input transformer circuitry 14 may be used to provide loadline transformation.

The input switching circuitry 16 receives and forwards the firstdifferential RF switching signal to provide a first differential RFinput signal based on the mode select signal MSS, the input switchingcircuitry 16 receives and forwards the second differential RF switchingsignal to provide a second differential RF input signal based on themode select signal MSS, and the input switching circuitry 16 receivesand forwards the M^(TH) differential RF switching signal to provide anM^(TH) differential RF input signal based on the mode select signal MSS.The first differential RF input signal includes a first positive-side RFinput signal IS1P and a first negative-side RF input signal IS1N, thesecond differential RF input signal includes a second positive-side RFinput signal IS2P and a second negative-side RF input signal IS2N, andthe M^(TH) differential RF input signal includes an M^(TH) positive-sideRF input signal ISMP and an M^(TH) negative-side RF input signal ISMN.The first positive-side RF input signal IS1P may be phase-shifted fromthe first negative-side RF input signal IS1N by about 180 degrees, thesecond positive-side RF input signal IS2P may be phase-shifted from thesecond negative-side RF input signal IS2N by about 180 degrees, and theM^(TH) positive-side RF input signal ISMP may be phase-shifted from theM^(TH) negative-side RF input signal ISMN by about 180 degrees.

Depending on the mode select signal MSS, the input switching circuitry16 may receive and forward the first positive-side RF switching signalSS1P to provide the first positive-side RF input signal IS1P, andreceive and forward the first negative-side RF switching signal SS1N toprovide the first negative-side RF input signal IS1N. Alternatively,depending on the mode select signal MSS, the input switching circuitry16 may receive and forward the first positive-side RF switching signalSS1P to provide the first negative-side RF input signal IS1N, andreceive and forward the first negative-side RF switching signal SS1N toprovide the first positive-side RF input signal IS1P.

Similarly, depending on the mode select signal MSS, the input switchingcircuitry 16 may receive and forward the second positive-side RFswitching signal SS2P to provide the second positive-side RF inputsignal IS2P, and receive and forward the second negative-side RFswitching signal SS2N to provide the second negative-side RF inputsignal IS2N. Alternatively, depending on the mode select signal MSS, theinput switching circuitry 16 may receive and forward the secondpositive-side RF switching signal SS2P to provide the secondnegative-side RF input signal IS2N, and receive and forward the secondnegative-side RF switching signal SS2N to provide the secondpositive-side RF input signal IS2P. In general, the first differentialRF input signal and the second differential RF input signal are based onsplitting the transformer input signal TIS.

Further, depending on the mode select signal MSS, the input switchingcircuitry 16 may receive and forward the M^(TH) positive-side RFswitching signal SSMP to provide the M^(TH) positive-side RF inputsignal ISMP, and receive and forward the M^(TH) negative-side RFswitching signal SSMN to provide the M^(TH) negative-side RF inputsignal ISMN. Alternatively, depending on the mode select signal MSS, theinput switching circuitry 16 may receive and forward the M^(TH)positive-side RF switching signal SSMP to provide the M^(TH)negative-side RF input signal ISMN, and receive and forward the M^(TH)negative-side RF switching signal SSMN to provide the M^(TH)positive-side RF input signal ISMP. In general, the first differentialRF input signal, the second differential RF input signal, and up to andincluding the M^(TH) differential RF input signal are based on splittingthe transformer input signal TIS.

The differential RF power amplifier circuitry 18 receives and amplifiesthe first differential RF input signal to provide a first differentialRF output signal, receives and amplifies the second differential RFinput signal to provide a second differential RF output signal, andreceives an amplifies up to an including the M^(TH) differential RFinput signal to provide an M^(TH) differential RF output signal. Thefirst differential RF output signal includes the first positive-side RFoutput signal OS1P and the first negative-side RF output signal OS1N,the second differential RF output signal includes the secondpositive-side RF output signal OS2P and the second negative-side RFoutput signal OS2N, and the M^(TH) differential RF output signalincludes an M^(TH) positive-side RF output signal OSMP and an M^(TH)negative-side RF output signal OSMN. The first positive-side RF outputsignal OS1P may be phase-shifted from the first negative-side RF outputsignal OS1N by about 180 degrees, the second positive-side RF outputsignal OS2P may be phase-shifted from the second negative-side RF outputsignal OS2N by about 180 degrees, and the M^(TH) positive-side RF outputsignal OSMP may be phase-shifted from the M^(TH) negative-side RF outputsignal OSMN by about 180 degrees.

The output transformer circuitry 20 receives and combines the firstdifferential RF output signal, the second differential RF output signal,and up to and including the M^(TH) differential RF output signal toprovide the first transformer output signal TOS1, the second transformeroutput signal TOS2, and up to and including a K^(TH) transformer outputsignal TOSK. In one embodiment of the RF circuitry 10, during the firstoperating mode, the first transformer output signal TOS1 is based on acombination of the first differential RF output signal, the seconddifferential RF output signal, and up to and including the M^(TH)differential RF output signal that substantially reinforce one another;the second transformer output signal TOS2 is based on a combination ofthe first differential RF output signal, the second differential RFoutput signal, and up to and including the M^(TH) differential RF outputsignal that substantially cancel one another; and the K^(TH) transformeroutput signal TOSK is based on a combination of the first differentialRF output signal, the second differential RF output signal, and up toand including the M^(TH) differential RF output signal thatsubstantially cancel one another.

Further, in one embodiment of the RF circuitry 10, during the secondoperating mode, the first transformer output signal TOS1 is based on acombination of the first differential RF output signal, the seconddifferential RF output signal, and up to and including the M^(TH)differential RF output signal that substantially cancel one another; thesecond transformer output signal TOS2 is based on a combination of thefirst differential RF output signal, the second differential RF outputsignal, and up to and including the M^(TH) differential RF output signalthat substantially reinforce one another; and the K^(TH) transformeroutput signal TOSK is based on a combination of the first differentialRF output signal, the second differential RF output signal, and up toand including the M^(TH) differential RF output signal thatsubstantially cancel one another.

Additionally, in one embodiment of the RF circuitry 10, during theK^(TH) operating mode, the first transformer output signal TOS1 is basedon a combination of the first differential RF output signal, the seconddifferential RF output signal, and up to and including the M^(TH)differential RF output signal that substantially cancel one another; thesecond transformer output signal TOS2 is based on a combination of thefirst differential RF output signal, the second differential RF outputsignal, and up to and including the M^(TH) differential RF output signalthat substantially cancel one another; and the K^(TH) transformer outputsignal TOSK is based on a combination of the first differential RFoutput signal, the second differential RF output signal, and up to andincluding the M^(TH) differential RF output signal that substantiallyreinforce one another. In an exemplary embodiment of the RF circuitry10, M is an even number.

The input transformer circuitry 14 includes the first input transformerelement 22, the second input transformer element 24, and up to andincluding a M^(TH) input transformer element 112. The differential RFpower amplifier circuitry 18 includes the first positive-side RF poweramplifier 26, the first negative-side RF power amplifier 28, the secondpositive-side RF power amplifier 30, the second negative-side RF poweramplifier 32, and up to and including an M^(TH) positive-side RF poweramplifier 114 and an M^(TH) negative-side RF power amplifier 116. Theoutput transformer circuitry 20 includes the first output transformerelement 34, the second output transformer element 36, and up to andincluding an M^(TH) output transformer element 118. The first inputtransformer element 22 includes the first input primary leg 38 and thefirst input secondary leg 40. The second input transformer element 24includes the second input primary leg 42 and the second input secondaryleg 44. The M^(TH) input transformer element 112 includes an M^(TH)input primary leg 120 and an M^(TH) input secondary leg 122.

The first output transformer element 34 includes the first outputprimary leg 46, the first output alpha secondary leg 48, the firstoutput beta secondary leg 50, and up to and including a first outputomega secondary leg 124. The second output transformer element 36includes the second output primary leg 52, the second output alphasecondary leg 54, the second output beta secondary leg 56, and up to andincluding a second output omega secondary leg 126. The M^(TH) outputtransformer element 118 includes an M^(TH) output primary leg 128, anM^(TH) output alpha secondary leg 130, an M^(TH) output beta secondaryleg 132, and up to and including an M^(TH) output omega secondary leg134.

One end of the first input primary leg 38 is coupled to ground and anopposite end of the first input primary leg 38 receives the transformerinput signal TIS. One end of the second input primary leg 42 is coupledto ground and an opposite end of the second input primary leg 42receives the transformer input signal TIS. One end of the M^(TH) inputprimary leg 120 is coupled to ground and an opposite end of the M^(TH)input primary leg 120 receives the transformer input signal TIS. Assuch, the transformer input signal TIS is a single-ended signal and thepower provided by the transformer input signal TIS is split between theinput transformer elements 22, 24, 112. The first input secondary leg 40provides the first positive-side RF switching signal SS1P and the firstnegative-side RF switching signal SS1N. The first input transformerelement 22 uses magnetic coupling, electrostatic coupling, or bothbetween the first input primary leg 38 and first input secondary leg 40,such that the first input secondary leg 40 provides the firstdifferential RF switching signal based on transforming the transformerinput signal TIS. The phasing of the first input primary leg 38 andfirst input secondary leg 40 is such that the first positive-side RFswitching signal SS1P is about phase-aligned with the transformer inputsignal TIS.

The second input secondary leg 44 provides the second positive-side RFswitching signal SS2P and the second negative-side RF switching signalSS2N. The second input transformer element 24 uses magnetic coupling,electrostatic coupling, or both between the second input primary leg 42and the second input secondary leg 44, such that the second inputsecondary leg 44 provides the second differential RF switching signalbased on transforming the transformer input signal TIS. The phasing ofthe second input primary leg 42 and the second input secondary leg 44 issuch that the second positive-side RF switching signal SS2P is aboutphase-aligned with the transformer input signal TIS.

The M^(TH) input secondary leg 122 provides the M^(TH) positive-side RFswitching signal SSMP and the M^(TH) negative-side RF switching signalSSMN. The M^(TH) input transformer element 112 uses magnetic coupling,electrostatic coupling, or both between the M^(TH) input primary leg 120and the M^(TH) input secondary leg 122, such that the M^(TH) inputsecondary leg 122 provides the M^(TH) differential RF switching signalbased on transforming the transformer input signal TIS. The phasing ofthe M^(TH) input primary leg 120 and the M^(TH) input secondary leg 122is such that the M^(TH) positive-side RF switching signal SSMP is aboutphase-aligned with the transformer input signal TIS.

The first positive-side RF power amplifier 26 receives and amplifies thefirst positive-side RF input signal IS1P to provide the firstpositive-side RF output signal OS1P. The first negative-side RF poweramplifier 28 receives and amplifies the first negative-side RF inputsignal IS1N to provide the first negative-side RF output signal OS1N.The second positive-side RF power amplifier 30 receives and amplifiesthe second positive-side RF input signal IS2P to provide the secondpositive-side RF output signal OS2P. The second negative-side RF poweramplifier 32 receives and amplifies the second negative-side RF inputsignal IS2N to provide the second negative-side RF output signal OS2N.The M^(TH) positive-side RF power amplifier 114 receives and amplifiesthe M^(TH) positive-side RF input signal ISMP to provide the M^(TH)positive-side RF output signal OSMP. The M^(TH) negative-side RF poweramplifier 116 receives and amplifies the M^(TH) negative-side RF inputsignal ISMN to provide the M^(TH) negative-side RF output signal OSMN.

The first output primary leg 46 receives the first differential RFoutput signal, the second output primary leg 52 receives the seconddifferential RF output signal, and the M^(TH) output primary leg 128receives the M^(TH) differential RF output signal. Specifically, one endof the first output primary leg 46 receives the first positive-side RFoutput signal OS1P and an opposite end of the first output primary leg46 receives the first negative-side RF output signal OS1N. Further, oneend of the second output primary leg 52 receives the secondpositive-side RF output signal OS2P and an opposite end of the secondoutput primary leg 52 receives the second negative-side RF output signalOS2N. Additionally, one end of the M^(TH) output primary leg 128receives the M^(TH) positive-side RF output signal OSMP and an oppositeend of the M^(TH) output primary leg 128 receives the M^(TH)negative-side RF output signal OSMN.

One end of the first output alpha secondary leg 48 provides the firsttransformer output signal TOS1 and an opposite end of the first outputalpha secondary leg 48 is coupled to one end of the second output alphasecondary leg 54. An opposite end of the second output alpha secondaryleg 54 is coupled via any intermediary alpha secondary legs (not shown)to one end of the M^(TH) output alpha secondary leg 130. An opposite endof the M^(TH) output alpha secondary leg 130 is coupled to ground.Similarly, one end of the first output beta secondary leg 50 providesthe second transformer output signal TOS2 and an opposite end of thefirst output beta secondary leg 50 is coupled via any intermediary betasecondary legs (not shown) to one end of the M^(TH) output betasecondary leg 132. An opposite end of the M^(TH) output beta secondaryleg 132 is coupled to ground. Further, one end of the first output omegasecondary leg 124 provides the K^(TH) transformer output signal TOSK andan opposite end of the first output omega secondary leg 124 is coupledto one end of the second output omega secondary leg 126. An opposite endof the second output omega secondary leg 126 is coupled via anyintermediary omega secondary legs (not shown) to one end of the M^(TH)output omega secondary leg 134. An opposite end of the M^(TH) outputomega secondary leg 134 is coupled to ground.

As such, the first output alpha secondary leg 48, the second outputalpha secondary leg 54, and up to and including the M^(TH) output alphasecondary leg 130 are coupled in series to provide the first transformeroutput signal TOS1. The first output beta secondary leg 50, the secondoutput beta secondary leg 56, and up to and including the M^(TH) outputbeta secondary leg 132 are coupled in series to provide the secondtransformer output signal TOS2. The first output omega secondary leg124, the second output omega secondary leg 126, and up to and includingthe M^(TH) output omega secondary leg 134 are coupled in series toprovide the K^(TH) transformer output signal TOSK. Therefore, in thisembodiment, the first transformer output signal TOS1, the secondtransformer output signal TOS2, and up to and including the K^(TH)transformer output signal TOSK are single-ended signals.

FIG. 12 shows details of the differential RF power amplifier circuitry18 illustrated in FIG. 1 according to one embodiment of the differentialRF power amplifier circuitry 18. The differential RF power amplifiercircuitry 18 includes a first positive-side input stage 136, a firstnegative-side input stage 138, a second positive-side input stage 140, asecond negative-side input stage 142, a first positive-side output stage144, a first negative-side output stage 146, a second positive-sideoutput stage 148, a second negative-side output stage 150, andintermediate transformer circuitry 152. The intermediate transformercircuitry 152 may be used to provide load line transformation betweenthe input stages 136, 138, 140, 142 and the output stages 144, 146, 148,150.

The first intermediate transformer element 154 includes a firstintermediate primary leg 158 and a first intermediate secondary leg 160.The second intermediate transformer element 156 includes a secondintermediate primary leg 162 and a second intermediate secondary leg164. The first positive-side input stage 136 and the first negative-sideinput stage 138 receive and amplify the first positive-side RF inputsignal IS1P and the first negative-side RF input signal IS1N,respectively, to feed the first intermediate primary leg 158. The firstintermediate secondary leg 160 feeds the first positive-side outputstage 144 and the first negative-side output stage 146 based ontransforming the amplified first positive-side RF input signal IS1P andthe first negative-side RF input signal IS1N, respectively. The firstpositive-side output stage 144 and the first negative-side output stage146 apply output stage amplification to provide the first positive-sideRF output signal OS1P and the first negative-side RF output signal OS1N,respectively

The second positive-side input stage 140 and the second negative-sideinput stage 142 receive and amplify the second positive-side RF inputsignal IS2P and the second negative-side RF input signal IS2N,respectively, to feed the second intermediate primary leg 162. Thesecond intermediate secondary leg 164 feeds the second positive-sideoutput stage 148 and the second negative-side output stage 150 based ontransforming the amplified second positive-side RF input signal IS2P andthe second negative-side RF input signal IS2N, respectively. The secondpositive-side output stage 148 and the second negative-side output stage150 apply output stage amplification to provide the second positive-sideRF output signal OS2P and the second negative-side RF output signalOS2N, respectively.

FIG. 13 shows the RF circuitry 10 according to one embodiment of the RFcircuitry 10. The RF circuitry 10 illustrated in FIG. 13 does not showthe control circuitry 12, the input transformer circuitry 14, the inputswitching circuitry 16, and the differential RF power amplifiercircuitry 18 for simplification of the illustration. The RF circuitry 10includes the output transformer circuitry 20, a first FDD duplexer 166,a first transmit TDD harmonic filter 168, antenna switching andinterface circuitry 170, and a first antenna 172. The first transformeroutput signal TOS1 provides a first frequency division duplex (FDD)transmit signal FDDTX1 to the first FDD duplexer 166, which may forwardthe first FDD transmit signal FDDTX1 to the first antenna 172 via theantenna switching and interface circuitry 170 for transmission. Further,the first FDD duplexer 166 may receive and forward a first FDD receivesignal FDDRX1 from the first antenna 172 via the antenna switching andinterface circuitry 170. The first FDD duplexer 166 may enablesimultaneous transmission and reception of the first FDD transmit signalFDDTX1 and the first FDD receive signal FDDRX1. In this regard, thefirst transformer output signal TOS1 may be a full duplex transmitsignal and the first FDD receive signal FDDRX1 may be a full duplexreceive signal.

The second transformer output signal TOS2 provides a first time divisionduplex (TDD) transmit signal TDDTX1 to the first transmit TDD harmonicfilter 168, which may forward the first TDD transmit signal TDDTX1 tothe first antenna 172 via the antenna switching and interface circuitry170. The RF circuitry 10 may preclude simultaneous transmission andreception of the first TDD transmit signal TDDTX1 and a complementaryreceive signal (not shown). As such, the second transformer outputsignal TOS2 may be a half duplex transmit signal.

FIG. 14 shows the RF circuitry 10 according to an alternate embodimentof the RF circuitry 10. The RF circuitry 10 illustrated in FIG. 14 doesnot show the control circuitry 12, the input transformer circuitry 14,the input switching circuitry 16, and the differential RF poweramplifier circuitry 18 for simplification of the illustration. The RFcircuitry 10 includes the output transformer circuitry 20, the firsttransmit TDD harmonic filter 168, the antenna switching and interfacecircuitry 170, the first antenna 172, and a second transmit TDD harmonicfilter 174. The first transformer output signal TOS1 provides the firstTDD transmit signal TDDTX1 to the first transmit TDD harmonic filter168, which may forward the first TDD transmit signal TDDTX1 to the firstantenna 172 via the antenna switching and interface circuitry 170 fortransmission. The second transformer output signal TOS2 provides asecond TDD transmit signal TDDTX2 to the second transmit TDD harmonicfilter 174, which may forward the second TDD transmit signal TDDTX2 tothe first antenna 172 via the antenna switching and interface circuitry170 for transmission.

The RF circuitry 10 may preclude simultaneous transmission and receptionof the first TDD transmit signal TDDTX1 and a complementary receivesignal (not shown). As such, the first transformer output signal TOS1may be a half duplex transmit signal. Similarly, the RF circuitry 10 maypreclude simultaneous transmission and reception of the second TDDtransmit signal TDDTX2 and a complementary receive signal (not shown).As such, the second transformer output signal TOS2 may be a half duplextransmit signal. The first transformer output signal TOS1 may be in afirst communications band, which may be a highband communications band.The second transformer output signal TOS2 may be in a secondcommunications band, which may be a lowband communications band. Thesecond communications band may not overlap the first communicationsband. A center frequency of the first communications band may be greaterthan about two times a center frequency of the second communicationsband.

FIG. 15 shows the RF circuitry 10 according to an additional embodimentof the RF circuitry 10. The RF circuitry 10 illustrated in FIG. 15 doesnot show the control circuitry 12, the input transformer circuitry 14,the input switching circuitry 16, and the differential RF poweramplifier circuitry 18 for simplification of the illustration. The RFcircuitry 10 includes the output transformer circuitry 20, the first FDDduplexer 166, a second FDD duplexer 176, the antenna switching andinterface circuitry 170, and the first antenna 172. The firsttransformer output signal TOS1 provides the first FDD transmit signalFDDTX1 to the first FDD duplexer 166, which may forward the first FDDtransmit signal FDDTX1 to the first antenna 172 via the antennaswitching and interface circuitry 170 for transmission. Further, thefirst FDD duplexer 166 may receive and forward a first FDD receivesignal FDDRX1 from the first antenna 172 via the antenna switching andinterface circuitry 170. The first FDD duplexer 166 may enablesimultaneous transmission and reception of the first FDD transmit signalFDDTX1 and the first FDD receive signal FDDRX1. In this regard, thefirst transformer output signal TOS1 may be a full duplex transmitsignal and the first FDD receive signal FDDRX1 may be a full duplexreceive signal.

The second transformer output signal TOS2 provides the second FDDtransmit signal FDDTX2 to the second FDD duplexer 176, which may forwardthe second FDD transmit signal FDDTX2 to the first antenna 172 via theantenna switching and interface circuitry 170 for transmission. Further,the second FDD duplexer 176 may receive and forward a second FDD receivesignal FDDRX2 from the first antenna 172 via the antenna switching andinterface circuitry 170. The second FDD duplexer 176 may enablesimultaneous transmission and reception of the second FDD transmitsignal FDDTX2 and the second FDD receive signal FDDRX2. In this regard,the second transformer output signal TOS2 may be a full duplex transmitsignal and the second FDD receive signal FDDRX2 may be a full duplexreceive signal. The first transformer output signal TOS1 may be in afirst communications band, which may be a highband communications band.The second transformer output signal TOS2 may be in a secondcommunications band, which may be a lowband communications band. Thesecond communications band may not overlap the first communicationsband. A center frequency of the first communications band may be greaterthan about two times a center frequency of the second communicationsband.

FIG. 16 shows the RF circuitry 10 according to another embodiment of theRF circuitry 10. The RF circuitry 10 illustrated in FIG. 16 does notshow the control circuitry 12, the input transformer circuitry 14, theinput switching circuitry 16, and the differential RF power amplifiercircuitry 18 for simplification of the illustration. The RF circuitry 10includes the output transformer circuitry 20, the first FDD duplexer166, first transmit TDD harmonic filter 168, the second transmit TDDharmonic filter 174, the second FDD duplexer 176, the antenna switchingand interface circuitry 170, and the first antenna 172.

The first transformer output signal TOS1 provides the first FDD transmitsignal FDDTX1 to the first FDD duplexer 166, which may forward the firstFDD transmit signal FDDTX1 to the first antenna 172 via the antennaswitching and interface circuitry 170 for transmission. Further, thefirst FDD duplexer 166 may receive and forward a first FDD receivesignal FDDRX1 from the first antenna 172 via the antenna switching andinterface circuitry 170. The first FDD duplexer 166 may enablesimultaneous transmission and reception of the first FDD transmit signalFDDTX1 and the first FDD receive signal FDDRX1. In this regard, thefirst transformer output signal TOS1 may be a first full duplex transmitsignal and the first FDD receive signal FDDRX1 may be a first fullduplex receive signal.

The second transformer output signal TOS2 provides the first TDDtransmit signal TDDTX1 to the first transmit TDD harmonic filter 168,which may forward the first TDD transmit signal TDDTX1 to the firstantenna 172 via the antenna switching and interface circuitry 170 fortransmission. The third transformer output signal TOS3 provides a secondTDD transmit signal TDDTX2 to the second transmit TDD harmonic filter174, which may forward the second TDD transmit signal TDDTX2 to thefirst antenna 172 via the antenna switching and interface circuitry 170for transmission.

The RF circuitry 10 may preclude simultaneous transmission and receptionof the first TDD transmit signal TDDTX1 and a complementary receivesignal (not shown). As such, the second transformer output signal TOS2may be a first half duplex transmit signal. Similarly, the RF circuitry10 may preclude simultaneous transmission and reception of the secondTDD transmit signal TDDTX2 and a complementary receive signal (notshown). As such, the third transformer output signal TOS3 may be asecond half duplex transmit signal.

The fourth transformer output signal TOS4 provides the second FDDtransmit signal FDDTX2 to the second FDD duplexer 176, which may forwardthe second FDD transmit signal FDDTX2 to the first antenna 172 via theantenna switching and interface circuitry 170 for transmission. Further,the second FDD duplexer 176 may receive and forward the second FDDreceive signal FDDRX2 from the first antenna 172 via the antennaswitching and interface circuitry 170. The second FDD duplexer 176 mayenable simultaneous transmission and reception of the second FDDtransmit signal FDDTX2 and the second FDD receive signal FDDRX2. In thisregard, the fourth transformer output signal TOS4 may be a second fullduplex transmit signal and the second FDD receive signal FDDRX2 may be asecond full duplex receive signal.

The first full duplex transmit signal and the first half duplex transmitsignal may be in a first communications band, such that the first fullduplex transmit signal and the first half duplex transmit signal may behighband transmit signals. The second full duplex transmit signal andthe second half duplex transmit signal may be in a second communicationsband, such that the second full duplex transmit signal and the secondhalf duplex transmit signal may be lowband transmit signals. The secondcommunications band may not overlap the first communications band. Acenter frequency of the first communications band may be greater thanabout two times a center frequency of the second communications band.

FIG. 17 shows details of a portion 180 of the output transformercircuitry 20 illustrated in FIG. 2 according to one embodiment of theportion 180 of the output transformer circuitry 20. The portion 180 ofthe output transformer circuitry 20 includes the first output primaryleg 46 and the AC blocking circuit 182. The first output primary leg 46includes a first output primary sub-leg 184 and a second output primarysub-leg 186 which are coupled in series to provide the first outputprimary leg 46. The AC blocking circuit 182 is coupled between a DCsupply DCSUPPLY and a junction of the first output primary sub-leg 184and the second output primary sub-leg 186. As such, the first outputprimary leg 46 may provide part of load line transformation and thecombination of the DC supply DCSUPPLY, the AC blocking circuit 182, thefirst output primary sub-leg 184, and the second output primary sub-leg186 may provide collector bias to the first positive-side RF poweramplifier 26 (FIG. 2) and to the first negative-side RF power amplifier28 (FIG. 2).

FIG. 18 shows the RF circuitry 10 according to a further embodiment ofthe RF circuitry 10. The RF circuitry 10 illustrated in FIG. 18 does notshow the control circuitry 12, the input transformer circuitry 14, theinput switching circuitry 16, and the differential RF power amplifiercircuitry 18 for simplification of the illustration. The RF circuitry 10includes the output transformer circuitry 20, the first FDD duplexer166, the interface circuitry 170, the first antenna 172, and a 1P2Tswitch 188. The 1P2T switch 188 receives and selects either the firsttransformer output signal TOS1 or the second transformer output signalTOS2 to provide the FDD transmit signal FDDTX1 to the first FDD duplexer166. The first output alpha secondary leg 48 (FIG. 2) and the secondoutput alpha secondary leg 54 (FIG. 2) may provide a first load-lineconversion ratio for the differential RF power amplifier circuitry 18via the first transformer output signal TOS1. The first output betasecondary leg 50 (FIG. 2) and the second output beta secondary leg 56(FIG. 2) may provide a second load-line conversion ratio for thedifferential RF power amplifier circuitry 18 that is not equal to thefirst load-line conversion ratio. In this regard, the 1P2T switch 188may select one of two different load-line conversion ratios for thedifferential RF power amplifier circuitry 18. As a result, the load-lineconversion ratio may be selected to minimize power consumption of thedifferential RF power amplifier circuitry 18, depending on output powerfrom the differential RF power amplifier circuitry 18. Alternateembodiments of the RF circuitry 10 may include any number of transformeroutput signals TOS1, TOS2 feeding a single-pole any-throw switch toprovide any number of load-line conversion ratios to provide furtherflexibility to minimize power consumption of the differential RF poweramplifier circuitry 18.

Some of the circuitry previously described may use discrete circuitry,integrated circuitry, programmable circuitry, non-volatile circuitry,volatile circuitry, software executing instructions on computinghardware, firmware executing instructions on computing hardware, thelike, or any combination thereof. The computing hardware may includemainframes, micro-processors, micro-controllers, DSPs, the like, or anycombination thereof.

None of the embodiments of the present disclosure are intended to limitthe scope of any other embodiment of the present disclosure. Any or allof any embodiment of the present disclosure may be combined with any orall of any other embodiment of the present disclosure to create newembodiments of the present disclosure.

Those skilled in the art will recognize improvements and modificationsto the preferred embodiments of the present disclosure. All suchimprovements and modifications are considered within the scope of theconcepts disclosed herein and the claims that follow.

What is claimed is:
 1. Radio frequency (RF) circuitry comprising:differential RF power amplifier circuitry configured to: receive andamplify a first differential RF input signal to provide a first.differential RF output signal; and receive and amplify a seconddifferential RF input signal to provide a second differential RF outputsignal; and output transformer circuitry configured to provide a firsttransformer output signal and a second transformer output signal, suchthat: during a first operating mode, power provided by the firstdifferential RF output signal and power provided by the seconddifferential RF output signal substantially combine to provide power viathe first transformer output signal, wherein power provided via thesecond transformer output signal is essentially zero; and during asecond operating mode, power provided by the first differential RFoutput signal and power provided by the second differential RF outputsignal substantially combine to provide power via the second transformeroutput signal, wherein power provided via the first transformer outputsignal is essentially zero.
 2. The RF circuitry of claim 1 wherein theoutput transformer circuitry is further configured to receive andcombine the first differential RF output signal and the seconddifferential RF output signal to provide the first transformer outputsignal and the second transformer output signal, such that: during thefirst operating mode, the first transformer output signal is based on acombination of the first differential RF output signal and the seconddifferential RF output signal that substantially reinforce one another,and the second transformer output signal is based on a combination ofthe first differential RF output signal and the second differential RFoutput signal that substantially cancel one another; and during thesecond operating mode, the first transformer output signal is based on acombination of the first differential RF output signal and the seconddifferential RF output signal that substantially cancel one another, andthe second transformer output signal is based on a combination of thefirst differential RF output signal and the second differential RFoutput signal that substantially reinforce one another.
 3. The RFcircuitry of claim 1 wherein a plurality of operating modes includes thefirst operating mode and the second operating mode.
 4. The RF circuitryof claim 3 further comprising the control circuitry configured toreceive and split a transformer input signal, such that the firstdifferential RF input signal and the second differential RF input signalare based on the split transformer input signal, wherein the transformerinput signal is de-multiplexed to provide the first transformer outputsignal and the second transformer output signal.
 5. The RF circuitry ofclaim 4 wherein the transformer input signal is a single-ended signal.6. The RF circuitry of claim 4 further comprising input switchingcircuitry, such that: the input transformer circuitry is furtherconfigured to receive and split the transformer input signal to providea first differential RF switching signal and a second differential RFswitching signal; a mode select signal is based on a selected one of theplurality of operating modes; and the input switching circuitry isconfigured to: receive the mode select signal; receive the firstdifferential RF switching signal to provide the first differential RFinput signal based on the mode select signal; and receive the seconddifferential RF switching signal to provide the second differential RFinput signal based on the mode select signal.
 7. The RF circuitry ofclaim 6 wherein: the first differential RF switching signal has a firstpositive-side RF switching signal and a first negative-side RF switchingsignal; the second differential RF switching signal has a secondpositive-side RF switching signal and a second negative-side RFswitching signal; the first differential RF input signal has a firstpositive-side RF input signal and a first negative-side RF input signal;the second differential RF input signal has a second positive-side RFinput signal and a second negative-side RF input signal; during thefirst operating mode, the input switching circuitry is furtherconfigured to: forward the first positive-side RF switching signal toprovide the first positive-side RF input signal; forward the firstnegative-side RF switching signal to provide the first negative-side RFinput signal; forward the second positive-side RF switching signal toprovide the second positive-side RF input signal; and forward the secondnegative-side RF switching signal to provide the second negative-side RFinput signal; and during the second operating mode, the input switchingcircuitry is further configured to: forward the first positive-side RFswitching signal to provide the first positive-side RF input signal;forward the first negative-side RF switching signal to provide the firstnegative-side RF input signal; forward the second positive-side RFswitching signal to provide the second negative-side RF input signal;and forward the second negative-side RF switching signal to provide thesecond positive-side RF input signal.
 8. The RF circuitry of claim 6wherein the input transformer circuitry comprises: a first inputtransformer element having: a first input primary leg configured toreceive the transformer input signal; and a first input secondary legconfigured to provide the first differential RF switching signal basedon transforming the transformer input signal; and a second inputtransformer element having: a second input primary leg configured toreceive the transformer input signal; and a second input secondary legconfigured to provide the second differential RF switching signal basedon transforming the transformer input signal.
 9. The RF circuitry ofclaim 3 wherein: the first differential RF input signal has a firstpositive-side RF input signal and a first negative-side RF input signal;the second differential RF input signal has a second positive-side RFinput signal and a second negative-side RF input signal; the firstdifferential RF output signal has a first positive-side RF output signaland a first negative-side RF output signal; the second differential RFoutput signal has a second positive-side RF output signal and a secondnegative-side RF output signal; and the differential RF power amplifiercircuitry comprises: a first positive-side RF power amplifier configuredto receive and amplify the first positive-side RF input signal toprovide the first positive-side RF output signal; a first negative-sideRF power amplifier configured to receive and amplify the firstnegative-side RF input signal to provide the first negative-side RFoutput signal; a second positive-side RF power amplifier configured toreceive and amplify the second positive-side RF input signal to providethe second positive-side RF output signal; and a second negative-side RFpower amplifier configured to receive and amplify the secondnegative-side RF input signal to provide the second negative-side RFoutput signal.
 10. The RF circuitry of claim 3 wherein the outputtransformer circuitry comprises: a first output transformer elementhaving: a first output primary leg configured to receive the firstdifferential RF output signal; a first output alpha secondary legconfigured to provide a portion of the first transformer output signalbased on transforming the first differential RF output signal; and afirst output beta secondary leg configured to provide a portion of thesecond transformer output signal based on transforming the firstdifferential RF output signal; and a second output transformer elementhaving: a second output primary leg configured to receive the seconddifferential RF output signal; a second output alpha secondary legcoupled in series with the first output alpha secondary leg andconfigured to provide a portion of the first transformer output signalbased on transforming the second differential RF output signal; and asecond output beta secondary leg coupled in series with the first outputbeta secondary leg and configured to provide a portion of the secondtransformer output signal based on transforming the second differentialRF output signal.
 11. The RF circuitry of claim 3 wherein the firsttransformer output signal is a single-ended signal and the secondtransformer output signal is a single-ended signal.
 12. The RF circuitryof claim 3 wherein: the plurality of operating modes includes the firstoperating mode, the second operating mode, and up to and including aK^(TH) operating mode; the differential RF power amplifier circuitry isfurther configured to receive and amplify each of a plurality ofdifferential RF input signals to provide a corresponding each of aplurality of differential RF output signals; the plurality ofdifferential RF input signals includes the first differential RF inputsignal, the second differential RF input signal, and up to and includingan M^(TH) differential RF input signal; the plurality of differential RFoutput signals includes the first differential RF output signal, thesecond differential RF output signal, and up to and including an M^(TH)differential RF output signal; a plurality of transformer output signalsincludes the first transformer output signal, the second transformeroutput signal, and up to and including a K^(TH) transformer outputsignal; the output transformer circuitry is further configured toreceive and combine the plurality of differential RF output signals toprovide the plurality of transformer output signals, such that: duringthe first operating mode, the first transformer output signal is basedon a combination of the plurality of differential RF output signals thatsubstantially reinforce one another, the second transformer outputsignal is based on a combination of the plurality of differential RFoutput signals that substantially cancel one another, and the K^(TH)transformer output signal is based on a combination of the plurality ofdifferential RF output signals that substantially cancel one another;during the second operating mode, the first transformer output signal isbased on a combination of the plurality of differential RF outputsignals that substantially cancel one another, the second transformeroutput signal is based on a combination of the plurality of differentialRF output signals that substantially reinforce one another, and theK^(TH) transformer output signal is based on a combination of theplurality of differential RF output signals that substantially cancelone another; and during the K^(TH) operating mode, the first transformeroutput signal is based on a combination of the plurality of differentialRF output signals that substantially cancel one another, the secondtransformer output signal is based on a combination of the plurality ofdifferential RF output signals that substantially cancel one another,and the K^(TH) transformer output signal is based on a combination ofthe plurality of differential RF output signals that substantiallyreinforce one another.
 13. The RF circuitry of claim 12 wherein M is aneven number.
 14. The RF circuitry of claim 3 wherein: a mode selectsignal is based on a selected one of the plurality of operating modes;the plurality of operating modes further includes a reduced output poweroperating mode; the differential RF power amplifier circuitry isconfigured to: receive the mode select signal; during the firstoperating mode, provide a first total output power based on the modeselect signal; during the second operating mode, provide a second totaloutput power based on the mode select signal; and during the reducedoutput power operating mode, provide a reduced total output power basedon the mode select signal; the reduced total output power is less thanthe first total output power; and the reduced total output power is lessthan the second total output power.
 15. The RF circuitry of claim 3wherein: the first transformer output signal is a full duplex transmitsignal; and the second transformer output signal is a half duplextransmit signal.
 16. The RF circuitry of claim 3 wherein: the firsttransformer output signal is a half duplex transmit signal in a firstcommunications band; and the second transformer output signal is a halfduplex transmit signal in a second communications band, which does notoverlay the first communications band.
 17. The RF circuitry of claim 3wherein: the first transformer output signal is a full duplex transmitsignal in a first communications band; and the second transformer outputsignal is a full duplex transmit signal in a second communications band,which does not overlay the first communications band.
 18. The RFcircuitry of claim 3 wherein the first transformer output signal isassociated with a first load-line conversion ratio for the differentialRF power amplifier circuitry and the second transformer output signal isassociated with a second load-line conversion ratio for the differentialRF power amplifier circuitry, such that the first load-line conversionratio is not equal to the second load-line conversion ratio.
 19. Amethod comprising: selecting one of a plurality of operating modes,which includes a first operating mode and a second operating mode;receiving and amplifying a first differential radio frequency (RF) inputsignal to provide a first differential RF output signal; receiving andamplifying a second differential RF input signal to provide a seconddifferential RF output signal; providing output transformer circuitry;and providing a first transformer output signal and a second transformeroutput signal from the output transformer circuitry, such that: duringthe first operating mode, power provided by the first differential RFoutput signal and power provided by the second differential RF outputsignal substantially combine to provide power via the first transformeroutput signal, wherein power provided via the second transformer outputsignal is essentially zero; and; and during the second operating mode,the power provided by the first differential RF output signal and thepower provided by the second differential RF output signal substantiallycombine to provide power via the second transformer output signal,wherein power provided via the first transformer output signal isessentially zero.